Small Building Code 2004
Short Description
Building Code ( Trinidad )...
Description
Trinidad & Tobago Small Building Code
First edition Page 1/179
Trinidad and Tobago
Small Building Code
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 2/179
The Committee, which has prepared this code, include the followings : Mr. Fenrick De Four
National Physical Planning Commission (Chairman)
Mr. Zanim Ali
Ministry of Works
Mr. Burnell Austin
Ministry of Local Government
Mr. Stephen Basdeo
National Emergency Management Authority
Mr. Kenrick Bethelmy
Trinidad and Tobago Fire Services
Mr. Mohan Bholasingh
Public health inspector - Chairman of Association
Mr. Robert Blache-Fraser
Trinidad & Tobago Institute of Architects
Mr. Jack Bynoe
Board of Architecture of Trinidad & Tobago
Mr. Peter Bynoe
Trinidad & Tobago Institute of Architects
Dr. Richard Clarke
Board of Engineering of Trinidad & Tobago
Mr. J. Holgar Hackshaw
Land Settlements Agency
Mr. Abdul Latiff Mr. Alan Lodwick
John Donaldson Technical Institute Ministry of Housing and Settlements – Town and Country Planning division
Mr. Jameel Mohammed
Ministry of Local Government
Mr. Graham Montano
Ministry of Works
Dr. Jeffrey M. Phillips
Board of Engineering of Trinidad & Tobago
Dr. Jean M. Picchiottino
Board of Engineering of Trinidad & Tobago
Mr. Francis Pierre
Ministry of Local Government, Sangre Grande Regional Corporation
Mr. Richard Sahadath Mr. Madan Singh Mr. Edwin Yuk Low
Ministry of Works Public health inspector – Ministry of Health City Engineer, Port of Spain City Corporation
Mr. Errol Rampaul
Trinidad & Tobago Bureau of Standards (Secretary 1)
Mr. Ishmael A. Soobrattee
Trinidad & Tobago Bureau of Standards (Secretary 2)
Mr. Aleksandar Brkovic
Trinidad & Tobago Bureau of Standards (Secretary 3)
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 3/179
Content 1 SCOPE ........................................................................................................................................................................ 3 2 NORMATIVE REFERENCES ............................................................................................................................. 3 3 TERMS AND DEFINITIONS ................................................................................................................................ 3 4
GENERAL CONSTRUCTION........................................................................................................................... 3 4.1 PRINCIPLE ....................................................................................................................................................... 3 4.1.1 Site preparation ........................................................................................................................................... 3 4.1.2 Site clearance............................................................................................................................................... 3 4.1.3 Material storage .......................................................................................................................................... 3 4.1.4 Batter boards ............................................................................................................................................... 3 4.1.5 Driveways and paving............................................................................................................................... 3 4.1.6 Earth works................................................................................................................................................ 3 4.1.7 Earthquake considerations ........................................................................................................................ 3 4.1.8 Hurricane considerations ......................................................................................................................... 3 4.1.9 Roofs........................................................................................................................................................... 3 4.1.10 Windows and doors .................................................................................................................................. 3 4.2 DESIGN CRITERIA.................................................................................................................................................. 3 4.2.1 Conventional design.................................................................................................................................. 3 4.2.2 Engineered design ..................................................................................................................................... 3 4.2.3 Dead load................................................................................................................................................... 3 4.2.4 Live load..................................................................................................................................................... 3 COASTAL/TIDAL ........................................................................................................................................................... 3 4.2.5 Roof load. ................................................................................................................................................... 3 4.2.6 Lateral load design.................................................................................................................................... 3 4.2.7 Load factors ............................................................................................................................................... 3 4.2.8 Deflection ................................................................................................................................................... 3 4.3 MINIMAL REQUIREMENTS .................................................................................................................................... 3 4.3.1 Site address ................................................................................................................................................ 3 4.3.2 Light............................................................................................................................................................ 3 4.3.3 Ventilation.................................................................................................................................................. 3 4.3.4 Minimum room sizes.................................................................................................................................. 3 4.3.5 Ceiling height............................................................................................................................................. 3 4.3.6 Minimum passage...................................................................................................................................... 3 4.3.7 Sanitation ..................................................................................................................................................... 3 4.3.8 Toilet, bath and shower spaces................................................................................................................. 3 4.3.9 Glazing ....................................................................................................................................................... 3 4.3.10 Enclosed car ports.................................................................................................................................... 3 4.3.11 Emergency escape and rescue openings................................................................................................. 3 4.3.12 Exits ........................................................................................................................................................... 3 4.3.13 Landings on stairways.............................................................................................................................. 3 4.3.14 Pedestrian ramps...................................................................................................................................... 3 4.3.15 Stairways................................................................................................................................................... 3 4.3.16 Handrails .................................................................................................................................................. 3 4.3.17 Guards....................................................................................................................................................... 3 4.3.18 Smoke detectors ........................................................................................................................................ 3 4.3.19 Foam plastic ............................................................................................................................................. 3 4.3.20 Flame spread and smoke density............................................................................................................. 3 4.3.21 Insulation .................................................................................................................................................. 3 4.3.22 Dwelling unit separation.......................................................................................................................... 3 4.3.23 Moisture vapour barriers......................................................................................................................... 3 4.3.24 Protection against decay.......................................................................................................................... 3 4.3.25 Protection against termites ...................................................................................................................... 3
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 4/179
4.3.26 Flood resistant construction .................................................................................................................... 3 4.3.27 Coastal high hazard areas ....................................................................................................................... 3 4.4 BASIC MATERIALS................................................................................................................................................ 3 4.4.1 Reinforced Concrete.................................................................................................................................. 3 4.4.2 Timber ........................................................................................................................................................ 3 4.4.3 Metal........................................................................................................................................................... 3 4.5 ALTERNATE MATERIALS AND TYPES OF CONSTRUCTION ................................................................................... 3 4.5.1 General....................................................................................................................................................... 3 4.5.2 Standards ................................................................................................................................................... 3 5
FOUNDATIONS .................................................................................................................................................... 3 5.1 GENERAL ............................................................................................................................................................. 3 5.1.1 Load bearing walls and columns.............................................................................................................. 3 5.1.2 Reinforcement ............................................................................................................................................ 3
6
VERTICAL STRUCTURES................................................................................................................................ 3 6.1 CONCRETE AND MASONRY ................................................................................................................................. 3 6.1.1 Masonry block walls .............................................................................................................................. 3 6.1.2 Columns, beams and shear panel structure............................................................................................. 3 6.1.3 Framed structure ....................................................................................................................................... 3 6.2 TIMBER ................................................................................................................................................................ 3 6.2.1 Identification and grade............................................................................................................................ 3 6.2.2 Exterior walls............................................................................................................................................. 3 6.2.3 Interior load bearing walls ....................................................................................................................... 3 6.2.4 Interior non-bearing walls........................................................................................................................ 3 6.2.5 Drilling and notching-studs ...................................................................................................................... 3 6.2.6 Headers ...................................................................................................................................................... 3 6.2.7 Cripple walls.............................................................................................................................................. 3 6.2.8 Wall bracing............................................................................................................................................... 3 6.2.9 Structure..................................................................................................................................................... 3 6.2.10 Cladding.................................................................................................................................................... 3 6.3 METAL.................................................................................................................................................................. 3 6.3.1 MS beams and profiles .............................................................................................................................. 3 6.4 MIXED CONSTRUCTION ....................................................................................................................................... 3
7
FLOOR SYSTEMS................................................................................................................................................ 3 7.1 CONCRETE FLOOR SLABS .................................................................................................................................... 3 7.1.1 Layout......................................................................................................................................................... 3 7.1.2 Finishing .................................................................................................................................................... 3 7.1.3 Services....................................................................................................................................................... 3 7.2 TIMBER ................................................................................................................................................................ 3 7.2.1 Identification & Grade .............................................................................................................................. 3 7.2.2 General....................................................................................................................................................... 3 7.2.3 Floor sheathing.......................................................................................................................................... 3 7.3 METAL ................................................................................................................................................................. 3 7.3.1 MS steel beam ............................................................................................................................................ 3
8
ROOF ASSEMBLIES ........................................................................................................................................... 3 8.1 ROOF STRUCTURE ............................................................................................................................................... 3 8.1.1 Concrete roof structure ............................................................................................................................. 3 8.1.2 Timber ........................................................................................................................................................ 3 8.1.3 Metal........................................................................................................................................................... 3 8.2 ROOF COVERING ................................................................................................................................................. 3 8.2.1 Weather protection .................................................................................................................................... 3 8.2.2 Materials .................................................................................................................................................... 3 8.2.3 Requirements for material roof covering................................................................................................. 3
ANNEX « A » .................................................................................................................................................................. 3 A.1 APPLICATION TO BUILD ..................................................................................................................................... 3 A.1.1 General ...................................................................................................................................................... 3
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 5/179
A.1.2 Form of application to build .................................................................................................................... 3 A.1.3 Approval in part ........................................................................................................................................ 3 A.2 APPROVALS ........................................................................................................................................................ 3 A.3 INSPECTIONS....................................................................................................................................................... 3 A.3.1 Procedure .................................................................................................................................................. 3 A.4 COMPLETION CERTIFICATE ................................................................................................................................ 3 A.5 COMPLIANCE ...................................................................................................................................................... 3 A.6 ALTERNATE MATERIALS AND TYPES OF CONSTRUCTION ................................................................................. 3 A.6.1 Application................................................................................................................................................. 3
Note: All modifications on the next edition index “x” will be changed in ITALIC
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 6/179
FOREWORD The Trinidad & Tobago Small building Code was declared a National Standard on ------------------, 2004 After the draft finalized by the Small Building Committee had been approved by the Trinidad & Tobago Bureau of Standards. The preparation of this code/standard arose out of the need to improve the quality of Trinidad and Tobago’s house while assuring that the safety of the structure is maintained. In the preparation of this code, extensive use has been made of the Parts of the Caribbean Uniform Building Code (CUBIC) which deals with small buildings. The CUBIC is at this time being considered for revision and the management Committee for the revision project has elected to make use of the International Code Council Inc., of the U.S.A. in the provision of base documentation for the revision of CUBIC. In like manner for this code use has been made of the I.B.C. year 2000. International Residential Code Final Draft 1998. The small Building Code is a document which has been put together by several public and private organisations in Trinidad and Tobago to streamline the approval and construction of small, non complex building structures and ensure that work is completed in a manner that conforms to acceptable standards. The drafting of the code document has been managed by the Board of Engineering of Trinidad & Tobago, sponsored by the Joint Consultative Council in the Construction Industry and the Interim National Physical Planning Commission with the support and active participation of the Trinidad & Tobago Bureau of Standards. The first edition of this code provides simple guidelines for the construction of small buildings (residential, office or light industrial) where use is made of concrete foundations, masonry block walls or timber and metal frame or wooden roofing system. Future editions of this code will cover all types of small buildings constructed with concrete, masonry block walls, steels and timber, metal or any combination of these Future editions of this code will cover also openings, floor, ceiling and wall finishing , burglar-proofing to make with the plumbing and the electrical codes of Trinidad and Tobago a complete collection to cover the Small Buildings.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 7/179
1 Scope 1.1 These provisions shall be known as the “Trinidad and Tobago Small Building Code” and shell refer to herein as “This Code”. 1.2 The provisions in this code shall apply to the construction, alteration, movement, enlargement, repair, equipment, use occupancy, location, maintenance, removal and demolition of buildings, for single or multiple family residential or general purpose use of not more than two stories in height and with a gross floor area of three hundred square metres (300m2) or less. 1.3 This code is intended to provide minimum requirements to safeguard life, limb, health and public welfare. It calls for minimum requirements for building materials in common use and takes into consideration the need for protection against wind and earthquake. 1.4 Sufficient detail is provided to allow for the adequate preparation of plans for buildings under normal environmental conditions. Regulatory authorities would deal with approvals on the basis of adherence to the requirements of this code. (see Annex A – Administration and Enforcement) 1.5 The builder/designer is advised to seek assistance from registered professionals in the design and construction of wind and earthquake resistant structures for buildings outside the scope of this code and/or for special application or other than normal environmental conditions.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
2
First edition Page 8/179
Normative references
This chapter lists the standards that are referenced in various sections of this document.
ASTM American Society for Testing and Materials 100 Barr Harbor Drive West Conshohocken, PA 19428
Standard number
reference
ASTM A 755M - 94
ASTM B 101-96 ASTM C 34-96 ASTM C 406 - 89 ASTM C 652-95a ASTM C 1167 - 94a
Title
Code reference
Specification for steel sheet, metallic coated by the hot dip process and pre-painted by the coil-coating process for exterior exposed building products Lead coated copper sheets Specification bearing wall tile.
for
structural
Roof materials
Roof materials clay
load-
Specification for roofing slate Specification for hollow brick (Hollow masonry units made from clay or shale) Specification for clay roof tiles
Hollow masonry blocks Roof materials Hollow masonry blocks Roof materials
ASTM D 224 - 89
Specification for smooth surfaced asphalt roll roofing (Organic felt)
Roof materials
ASTM D 225-95
Asphalt shingles with mineral granules
(Organic felt) surfaced
Roof materials
ASTM D 226-94
Specification for asphalt-saturated organic felt used in roofing and water proofing
Roof materials
ASTM D 227-97a
Coal tar saturated organic felt used in roofing and waterproofing
Roof materials
Specification for coal tar saturated organic felt used in roofing and water proofing
Roof materials
ASTM D 312-84
Specification for asphalt used in roofing
Roof materials
ASTM D 450-96
Coal tar pitch used in roofing, dampproofing and waterproofing
Roof materials
ASTM D 249-89 (96)
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code ASTM D 1863-93 (96)
First edition Page 9/179 Mineral aggregate used in built up roofs
Roof materials
ASTM D 2178-97a
Asphalt glass felt used in roofing and waterproofing
Roof materials
ASTM D 2626-97a
Asphalt saturated and coated organic felt base sheet used in roofing
Roof materials
ASTM D 3462-97a
Asphalt shingles made from glass felt and surfaced with mineral granules
Roof materials
ASTM D 3909-97a
Asphalt roll roofing (Glass felt) surfaced with mineral granules
Roof materials
ASTM D 4601-97a
Asphalt coated glass fibre base sheet used in roofing
Roof materials
ASTM D 4869-88
Asphalt saturated organic felt underlay used in roofing
Roof materials
ASTM D 4897-97a
Asphalt coated glass fibre venting base sheet used in roofing
Roof materials
ASTM D 4990-97a
Coal tar glass felt used in roofing and waterproofing
Roof materials
ASTM E 84-91a
Test method for surface characteristics for building materials
Foam plastic
burning
Flame spread smoke density
and
Insulation ASTM E 90-90
Test method for laboratory measurement of airborne sound transmission loss of building partitions
ASTM E 96-92
Standard test methods for water vapour transmission of materials
ASTM E 119-88
Test methods for fire tests of building construction and materials
Dwelling unit separation
ASTM E 492-90 (96)
Test method for laboratory measurement of impact sound transmission through floor ceiling assemblies using the tapping machine
Dwelling unit separation
ASTM E 814-94b
Test method for fire tests of through penetration fire stops
Dwelling unit separation
ASTM E 970-94a
Standard test method for critical radiant flux of exposed attic floor insulation using a radiant heat energy source
Insulation
ASTM E 1300-97
Standard practice for determining the minimum thickness and type of glass required to resist a specified load
Glazing
File # Small building code 2004_draft
Date 01 July, 2004
Dwelling unit separation
Moisture vapour barriers
Trinidad & Tobago Small Building Code
First edition Page 10/179
AWPA American Wood-Preservers Association PO Box 5690 Granbury, Texas 76049
Standard reference number
Title
Code reference
C1-90
All timber products- Preservative treatment by pressure processes
C15-90
Wood for commercial-residential construction- Preservative treatment by pressure processes
Protection against termites
BS British Standards
Standard reference number BS EN 490 : 1994
Title
Code reference
Concrete roofing tiles and fittings. Product specifications.
Roof materials
CPSC Consumer Product Safety Commission 4330 East West Highway Bethesda, MD 20814-4408
Standard number
reference
Title
Code reference
CPSC 16-CFR, 1201-77
part
Safety standard for architectural glazing
Glazing
CPSC 16-CFR 1209-79
part
Interim safety cellulose insulation
Insulation
CPSC 1404
part
16-CFR
File # Small building code 2004_draft
standard
for
Cellulose insulation
Date 01 July, 2004
Insulation
Trinidad & Tobago Small Building Code
First edition Page 11/179
CUBIC
Standard reference number
Title
Code reference
IRC International Residential Code for One and Two Family Dwellings Doubletree Hotel 3050 Bristol Street Costa Mesa, CA 92626
Standard reference number
Title
Code reference
Title
Code reference
ISO Case postale 56 CH- 1211 Geneva, 20 Switzerland
Standard reference number STD Version 1
STD template for the preparation of normative-type documents.
Presentation of building code".
the "Small
Reference manual.
TTS Trinidad and Tobago Bureau of Standards Trincity Industrial Estate Macoya, Tunapuna, Trinidad
Standard reference number
File # Small building code 2004_draft
Title
Code reference
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 12/179 Code of practice for the design and construction of septic tanks and associated secondary treatment and disposal system.
Sanitation
TTS 16 35 508
Specification for load masonry concrete units.
bearing
Hollow masonry blocks
TTS 16 35 509
Specification for non load bearing concrete masonry units.
Hollow masonry blocks
TTS 16 80 400: 1991
TTS 587:2003
Hollow clay block –vertical core
TTS 588:2003
Hollow clay block –horizontal core
TTS 16 35 511: 1998
Specification for corrugated galvanised and aluzinc coated steel sheets for roofing and general purpose.
TTS 171 TTS 583:2000
Electrical code
Roof materials
Dwelling unit separation
Carbon steel bars for the reinforcement of concrete Specification
Basic materials
ULC Underwriters Laboratories of Canada 7 Crouse Road Scarborough, Ontario, Canada MIR 3A9
Standard reference number S102.2 - M88
Title
Code reference
Standard method of test for surface burning characteristics of flooring, floor covering and miscellaneous materials and assembly
File # Small building code 2004_draft
Date 01 July, 2004
Insulation
Trinidad & Tobago Small Building Code
First edition Page 13/179
3 Terms and definitions 3.1
Addition
An extension or increase in floor area or height of the building or structure.
3.2
Anchor
Metal rod, wire, or strap that secures masonry or any structure to its structural support.
3.3
Approved
Acceptable to the building official
3.4
Attic
The space between the ceiling beams of the top story and the roof rafters.
3.5
Balcony
An exterior floor projecting from and supported by a structure without additional independent supports.
3.6
Basement
That portion of a building, which is partly or completely below grade.
3.7
Building
Any structure used or intended for supporting or sheltering any use or occupancy
3.8
Cement plaster
A mixture of Portland or blended cement, and hydrated lime, masonry cement or plastic cement and aggregate and other approved materials as specified in the code.
3.9
Cladding
The exterior surface of the building envelope that is directly loaded by the wind.
3.10
Column
A member with a ratio of height to least lateral dimension exceeding 3, used primarily to support axial compressive load.
3.11
Concrete
A mixture of Portland cement or any other hydraulic cement, fine aggregate, coarse aggregate, and water, with or without admixture.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code 3.12
First edition Page 14/179
Construction documents
Written, graphic and pictorial documents prepared or assembled for describing the design, location and physical characteristics of the elements of the project necessary for obtaining a building permit. Construction drawings shall be drawn to an appropriate scale.
3.13
Dead loads
Consist of the weight of materials of construction incorporated into building, including but not limited to walls, floors, ceilings, stairways, built in partitions, finishes, cladding and other similarly incorporated architectural and structural items, and fixed service equipment, including the weight of cranes.
3.14
Diaphragm
A horizontal or nearly horizontal system acting to transmit lateral forces to the vertical resisting elements. When the term “diaphragm “ is used, it includes horizontal bracing systems.
3.15
Dwelling
A building, which contains one or two dwelling units used, intended or designed to be built, used, rented, leased, let or hired out to be occupied, or which are occupied for living purposes.
3.16
Dwelling unit
A single unit providing complete independent living facilities for one or more persons including permanent provisions for living, sleeping, eating, cooking and sanitation.
3.17
Emergency escape and rescue opening
An openable window, door, or other similar device that provides for a means of escape and access for rescue of and emergency.
3.18
Fibreboard
A fibrous, homogeneous panel made from lignocelluloses fibres (usually wood or cane) and having a density of less than 500kg/m3 and more than 160kg/m3.
3.19
Fire resistance
That property of material or their assemblies that prevents or retards the passage of excessive heat, hot gases or flames under conditions of use.
3.20
Fire resistance rating
The period of time a building or building component maintains the ability to confine a fire or continues to perform a given structural function or both.
3.21
Floor area (gross and net) a) Gross
The floor area within the inside perimeter of the exterior walls of the building under consideration, exclusive of vent shafts and courts, without deduction for corridor, stairways, closets, the thickness of the interior walls, columns or other features.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 15/179
b) Net The actual occupied area not including unoccupied accessory areas such as corridors, stairways and closets.
3.22
Guard
A building component or a system of building components located at or near the open sides of elevated walking surfaces that minimise the possibility of a fall from the walking surface to a lower level.
3.23
Gypsum board
Gypsum wallboard, gypsum sheathing, gypsum base for gypsum veneer plaster, exterior gypsum soffit board, pre-decorated gypsum board, or water- resistant gypsum baking board.
3.24
Habitable space
A space in a building for living, sleeping, eating or cooking. Bathrooms, toilet rooms, closets, hall, storage or utility spaces and similar areas are not considered habitable spaces.
3.25
Handrail
A horizontal or sloping rail intended for grasping by the hand for guidance or support.
3.26
Header
A masonry unit that connect two or more adjacent withes of masonry.
3.27
Interior finish
Interior finish includes interior wall and ceiling finish and floor finish.
3.28
Interior floor finish
The exposed floor surfaces of buildings including coverings applied over a finished floor or stair, including risers.
3.29
Interlayment
A layer of felt or non-bituminous saturated felt not less than 450mm wide, shingled between each course of a wood shake roof covering.
3.30
Joint
The linear opening in or between adjacent fire resistance rated assemblies that is designed to allow independent movement of the building, in any plane, caused by thermal, seismic, wind or any other loading.
3.31
Live loads
Those load produced by the use and occupancy of the building or other structure and d not include construction or environmental load such as wind load, rain load, earthquake load, flood load or dead load.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
3.32
First edition Page 16/179
Load factor
A factor that accounts for deviations of the actual load from the nominal load, for uncertainties in the analysis that transforms the load into a load effect, and for the probability that more than one extreme load will occur simultaneously. 3.33
Lot
A portion or parcel of land considered as a unit.
3.34
Masonry
A built up construction of building units or materials of clay, shale, concrete, glass, gypsum, stone, or other approved units bonded together with or without mortar or grout or other accepted method of joining.
3.35
Garage
Enclosed carport.
3.36
Mortar
A plastic mixture of approved cementations materials, fine aggregate and water used to bond masonry or other structural units.
3.37
Owner
Any person, agent, firm or corporation having a legal or equitable interest in the property.
3.38
Panel (part of the structure)
The section of a floor, wall, or roof comprised between the supporting frame of two adjacent rows of columns and girder or column bands of floor or roof construction.
3.39
Permit
An official document or certificate issued by the authority having jurisdiction that authorizes performance of a specified activity.
3.40
Pile foundations
Pile foundations consist of concrete or steel structural elements either driven into the ground or cast in place. Piles are relatively slender in comparison to their length, with lengths exceeding 12 times the least horizontal dimension. Piles derive their load carrying capacity through skin friction, through end bearing or a combination of both.
3.41
Pier foundations
Pier foundations consist of isolated masonry or cast in place concrete structural elements extending into firm materials. Piers are relatively short in comparison to their width, with lengths less than or equal to 12 times the least horizontal dimension of the pier. Piers derive their load-carrying capacity through skin friction, through end bearing or a combination of both.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code 3.42
First edition Page 17/179
Plain concrete
Structural concrete with no reinforcement or with less reinforcement than the minimum amount specified for reinforced concrete.
3.43
Plain masonry
Masonry in which the tensile resistance of the masonry is taken into consideration and the effect of stresses in reinforcement are neglected.
3.44
Plywood
A wood structural panel comprised of plies of wood veneer arranged in cross-aligned layers. The plies are bonded with an adhesive that cures on application of heat and pressure.
3.45
Preservative (treated wood)
Wood including plywood impregnated under pressure with compounds, which reduce their susceptibility to flame, spread to deterioration caused by fungi, insects, or marine borers.
3.46
Ramp
A walking surface that has a running slope steeper than 5%.
3.47
Registered professional
An individual who is registered or licensed to practice their respective profession as defined by the statutory requirement of the professional registration laws of the country in which the project is to be constructed.
3.48
Reinforced concrete
Structural concrete reinforced with no less than the minimum amounts of pre-stressing tendons non-prestressed reinforcement.
3.49
Roof assembly
A system designed to provide weather protection and resistance to design loads.
3.50
Roof covering
The covering applied to the roof deck for weather resistance, fire classification or appearance.
3.51
Roof covering system
The system consists of a roof covering and roof deck or a single component serving as both the roof covering and the roof deck.
3.52
Shear wall a) Ordinary reinforced masonry shear wall.
A masonry shear wall designed to resist lateral forces considering stresses in reinforcement.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 18/179
b) Wood A wall designed to resist lateral forces parallel to the plane of the wall.
3.53
Stair
A change in elevation, consisting in one or more risers.
3.54
Stairway
One or more flights of stairs, either exterior or interior, with the necessary landings and platforms connecting them, to form a continuous and uninterrupted passage from one level to another.
3.55
Stirrup
Reinforcement used to resist shear and torsion stresses in a structural member; typically bars, wires or welded wire fabric either single leg or bent into L, U or rectangular shapes and located perpendicular to or at an angle to longitudinal reinforcement.
3.56
Story
That portion of the building included between the upper surface of the floor and the upper surface of the floor or roof next above.
3.57
Structure
That which is built or constructed.
3.58
Tile
A ceramic surface unit, relatively thin in relation to facial area, made from clay or a mixture of clay or other ceramic materials.
3.59
Treated wood
Wood impregnated under pressure with compounds, which reduce their susceptibility to flame, spread or to deterioration caused by fungi, insects or marine borers.
3.60
Underlayment
One or more layers of felt, sheathing paper, non-bituminous saturated felt, or other approved materials over which a steep-slope roof covering is applied
3.61
Vapour barrier
A material having a good permeance rating such as foil, plastic sheeting, or insulation facing installed to resist the transmission of water vapour through the exterior envelope.
3.62
Ventilation
The natural or mechanical process of supplying conditioned or unconditioned air to, or removing such air from any space.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
3.63
First edition Page 19/179
Wall (load bearing) a) Any metal or wood stud that supports more than 1.50 kN/m of vertical load in addition to its own weight. b) Any masonry or concrete wall that supports more than 3 kN/m of vertical load in addition to its own weight.
3.64
Wall (non load bearing)
Any wall that is not a load-bearing wall.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4
First edition Page 20/179
General construction
4.1
Principle
4.1.1
Site preparation
4.1.1.1
Preliminary investigation
Before any construction work commences, it shall be determined whether planning permission and other approvals would be required from the competent (relevant) authorities. A preliminary inspection of the site shall be undertaken so that preparation may be made for any problems or difficulties that may arise. This time should also be used to plan how the site will be organised so that a logical layout may emerge. 4.1.1.2
Checklist for site conditions
Completion of the checklist below will provide enough information about the site and its conditions to permit construction to begin. 4.1.1.2.1 Forms and documents a) Has planning permission been obtained? b) Is there a surveyor's or topographical drawing of the site? 4.1.1.2.2 Site c) The shape and sizes of plot conform to those shown on the layout plan d) Is easy access to the site available? e) The site can be adequately drained? f)
Have the location of all boundary markers been found?
g) Are water, sewage disposal facilities and an electricity supply available on site? h) Take note of the general topography of site and other physical conditions likely to cause hazards. i)
Is there evidence of termite infestation in the soil or trees?
j)
Will there be a need for the removal of large trees?
k) Is the area normally subject to land slippage? l)
Is there adequate natural provision for the removal of storm water i.e. drainage of water as a result of heavy rains or flooding.
m) Will construction endanger any of the public utility services? n) Determine the height of the water table if appropriate. o) Determine whether the soil is suitable for the construction of a soak-away pit. p) Determine the ground floor datum. q) Determine the depth of the foundation stratum, if feasible. r)
Select suitable areas for stockpiling aggregate.
s) Select an area for the location of a concrete mixer or for the hand-mixing of concrete. t)
Select location of a materials storage shed.
u) Are there existing structures to be removed or altered? Completion of the above checklist should highlight possible construction problems as well as the requirements of plant and materials. Where foundation problems are evident it is recommended that an engineer or any other appropriate professional be consulted.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.1.2
First edition Page 21/179
Site clearance
4.1.2.1 Care should be taken to preserve any trees on the site. Where it is necessary to remove any trees, special care shall be taken to remove, totally, all roots and stumps of the felled trees as well as any of the other remains from the site. Note: There may be statutory limitations on the extent to which large trees may be removed. Consult with the Ministry of Agriculture for further clarification.
4.1.2.2 The area where the building will be situated shall be stripped of topsoil. This material should be stock piled in a suitable area for later use during landscaping.
4.1.3
Material storage
4.1.3.1 Areas shall be allocated on the cleared site for the storage of materials. Coarse and fine aggregate for the mixing of concrete and mortar shall be placed in separate heaps in a location near to the concrete mixer or concrete mixing area. 4.1.3.2 Cement, nails and finished materials (groove ply, PVC pipe, galvanised sheeting etc.) requiring protected storage shall be stored in a shed, which is weather tight and has a wooden floor raised not less than four inches off the ground. 4.1.3.3
4.1.4
Reinforcement steel shall be stacked off the ground to reduce corrosion.
Batter boards
The building shall be properly set out on the site according to the building plan. Batter boards, which are horizontal boards parallel to the sides of the building and supported by vertical boards driven into the ground shall be erected in convenient locations near the four (or more) corners of the building, and to these boards should be transferred the building lines and levels for the project. 4.1.4.1 The floor level is usually marked on the batter boards and used as a permanent reference. All wall lines and levels shall be referred to these boards. Periodic checks shall be made to ensure that these boards have not been shifted from their intended positions.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code 4.1.5
First edition Page 22/179
Driveways and paving
4.1.5.1 The driveways and paving dealt with in this section are those suitable for use as driveways and parking areas for private cars and light goods vehicles only. Driveways shall be not less than 3m wide. 4.1.5.2 The choice of flexible (asphalt) or rigid (concrete) paving is largely influenced by the soil conditions at the site and the cost of driveway. Gravel driveways and paving are acceptable if adequate drainage is available and if the gravel or crushed rock is reasonably hard, free from clay, and would not be easily crushed by the light traffic. Adequate provision for drainage shall be made. 4.1.5.3 Where firm soils or rocks are present, any type of paving previously mentioned may be used. Where soft soils are present gravel or a flexible paving is recommended. 4.1.5.4 For all kinds of paving the topsoil shall be removed and replaced by a minimum of 150 mm of compacted, granular material. 4.1.5.5 For rigid paving, a concrete slab with a minimum thickness of 100 mm is required, reinforced by welded wire mesh of minimum 100 mm2/m wide in both directions, placed 25 mm below the top surface of the slab. Construction joints shall be created every 5 m. Note: A98, A142 and 150x150X4.5 BRC are acceptable. 4.1.5.6 For flexible paving a minimum thickness of 50 mm of asphalt (cold or hot mix) shall be applied and compacted by roller on an approved and adequate sub base.
4.1.6
Earth works
4.1.6.1
Site topography
4.1.6.1.1 The natural topography of the land should be maintained and any excavation or back filling that must be carried out (and deemed as necessary) should be kept to a minimum. This is necessary to maintain the natural vegetation, prevent landslides and flooding and preserve in general the natural environment. 4.1.6.1.2 It is essential therefore those buildings should be constructed in such a manner to compliment the natural topography of the site and not vice-versa.
4.1.6.2
Soil conditions
4.1.6.2.1 The characteristics of the site soil conditions shall be ascertained. If necessary, compaction shall be carried out in order to improve the bearing value of the soil. 4.1.6.2.2 Where expansive clay is encountered or where problem conditions are present, professional advice shall be sought before planning the foundation.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code 4.1.6.3
First edition Page 23/179
Excavations
4.1.6.3.1 Excavations for foundations shall be carried out along the building lines to the depth of the foundation stratum identified as suitable. 4.1.6.3.2 Excavations not exceeding 1.2 m in depth may generally be without planking and strutting, which is a system of braced timber walls erected against the faces of the excavation to prevent collapse. For excavations exceeding 1.2 m the extent of planking and strutting necessary shall be determined by the nature of the soil and the location of the water table. 4.1.6.3.3 Where collapse of the side of excavation is anticipated, all excavation in excess of 1.2 m in depth shall be planked and strutted. 4.1.6.3.4 Where the foundation is in rock, it shall be excavated at least 50 mm to provide a key for the foundations. 4.1.6.3.5 The bottom of all excavations shall be level and firm. Where loose materials are encountered, foundation bottoms shall be compacted by ramming. 4.1.6.3.6 Where excavations have been carried beyond their generally required depth, either by accident or design, the deep areas shall be back filled with compacted, adequate material or with Grade E concrete (see Table 6).
4.1.6.4
Back filling
4.1.6.4.1 Back filling shall not be carried out in dry rivers, natural drains, where water flows after heavy rains and along thalwegs (lowest areas in valleys). 4.1.6.4.2 Back filling around foundation walls and under floor slabs shall be carried out using only suitable, selected materials. Unless the floor slab is reinforced to act as a suspended slab, the depth of fill shall not exceed 1m. 4.1.6.4.3 Suitable fill material may be brought to the site or obtained from excavated material, provided always that such material is free of substantial amounts of clay or organic matter. 4.1.6.4.4 All backfill shall be well compacted in layers not exceeding 150 mm in thickness where compaction is by manual methods. Where mechanical compaction equipment is used, the thickness of layers may be increased to 225 mm. 4.1.6.4.5 Where back filling under floor slabs on grade has been effected using hard core, a 50 mm layer of sand shall be applied to the top of the compacted hard core to protect damp proof membranes from puncture.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.1.7
First edition Page 24/179
Earthquake considerations
4.1.7.1 Earthquake resistant construction
4.1.7.1.1
General
Trinidad and Tobago is in an earthquake zone and has experienced varying degrees of damage due to earthquakes. It is therefore essential that buildings are designed and constructed so that they have some resistance to the shaking or lateral forces produced by earthquakes.
4.1.7.1.2
Effect of soil type
a) The type of soil at the site may have a significant effect upon the resistance of the building to an earthquake. However for buildings within the scope of this code the effect of the soil type is not so significant provided that the building is not constructed on loose saturated sands, which may liquefy during an earthquake and cause collapse of the building. b) The earthquake may also, due to shaking of the ground, compact loose sand or fill material, and if a building is constructed on such material, the building will be damaged.
4.1.7.1.3
Effect of high seas
Buildings on coastal areas may suffer due to high waves produced by earthquakes, and therefore the sitting of the building in relation to the sea level needs to be considered. Professional advice shall therefore be sought in such cases.
4.1.7.1.4
Building shape
a) The success with which a building survives an earthquake is greatly affected by its shape in plan, the way the building is tied together and the quality of construction. b) Most buildings with a simple rectangular shape with no projections (or only short projections) perform well under earthquake conditions provided the construction is adequate. c) Long narrow buildings should be avoided by limiting the length to three times the width. If the building must be longer, then it should be divided into separate blocks with adequate separation. Figure 1 illustrates desirable and undesirable plan shapes. d) Rectangular buildings with well inter-connected cross walls are inherently strong and therefore desirable.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 25/179
Separation of Blgs to improve resistance
Desirable plans Long undesirable plans
Fig 1 - Plan of building proportion
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 26/179
Not enought shear panel Too narow
Too narow
Floor level
Not acceptable opening location Too many openings on the facade
400
1 000
2 020
1 100
400
Floor level
1 800mm min Shear panel
Fig 2 - Recommended location of wall openings
File # Small building code 2004_draft
Date 01 July, 2004
600mm minimum
Trinidad & Tobago Small Building Code
First edition Page 27/179
First floor
600 mm minimum
Ground level
First floor
Ground level
Fig 3 - Recommended location of wall openings for two storey building
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code 4.1.7.1.5
First edition Page 28/179
Appendages
Where buildings have decorative or functional additions or appendages such as window hoods, parapets and wall panels etc. extreme care must be taken to ensure that they are securely fixed, since many of such items tend to fall easily and may cause damage during an earthquake.
4.1.7.2
Rules for the construction of earthquake resistant buildings
It is recommended that the following rules be followed for the construction of buildings: 4.1.7.2.1
Masonry buildings
An important factor contributing to the earthquake resistance of masonry buildings is the detailing and placing of steel reinforcement. A registered professional should undertake the design of a reinforced concrete frame building. The reinforcing guide given in this section therefore must only be used for simple single storey buildings constructed of approved quality masonry blocks. For the minimum quantities of reinforcing steel to be used refer to SECTION 5 Vertical Structures. 4.1.7.2.2
Timber buildings
There are two additional areas of concern with respect to timber buildings: --- All corners and intersections must be adequately braced. --- Earthquake and hurricane forces tend to remove timber buildings from their supports by shaking. Because of this, sills shall be securely fastened to foundations. 4.1.7.2.3
Steel buildings
The natural ductility of steel protects the frame from severe damage. However, in many cases masonry block walls are used and the precautions already listed for these walls will apply. The wall reinforcement must now be anchored by welding to the steel columns and beams, or the steel frame encased in concrete in which case the wall reinforcement can be tied into the concrete cage encasing the steel frame.
4.1.7.3
Location of openings
4.1.7.3.1 The location and size of openings in walls have a significant effect upon the strength of a wall and its ability to resist earthquake forces. 4.1.7.3.2 Openings shall be located away from a corner by a clear distance of at least 1/4 of the height of the opening. It is recommended that the minimum distance be 400 mm. 4.1.7.3.3 The total length of the openings should not exceed 1/2 the length of the wall between consecutive cross walls (see Figure 2). 4.1.7.3.4 The horizontal distance between two openings should not be less than 1/2 the height of the shorter opening (see Figure 2). 4.1.7.3.5 For two storey buildings, the vertical distance from an opening to one directly above it shall not be less than 600mm, nor shall it be less than one half the width of the smaller opening.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.1.8
4.1.8.1
First edition Page 29/179
Hurricane considerations
Hurricane resistant construction
4.1.8.1.1
General
a) It is very important in Trinidad and Tobago to be ever conscious of the fact that the region lies in the hurricane belt. Because of this, hurricane resistant construction principles must be adhered to if safe buildings are to be erected. This section gives general principles for safe hurricane resistant design, and it is recommended that the details shown in these guidelines must be adhered in order to ensure safe construction. b) For the buildings within the scope of this document the areas most vulnerable to hurricane forces are the roofs, windows, walls and appendages. c) The underlying objective of hurricane resistant construction is to produce a building that will not collapse during a hurricane. The building must be standing and its occupants should be safe.
4.1.8.2
Rules for the construction of hurricane resistant buildings
4.1.8.2.1
Building site
a) Buildings sited in exposed areas (e.g. on the brow of a hill or near coastal areas) are most vulnerable, while those sheltered by natural topography are less vulnerable. Buildings sited in gullies or riverbeds are very vulnerable as they are subject to severe damage by floods caused by the heavy rains, which often accompany a hurricane. b) In sitting the building, therefore, steep slopes and edge of cliffs should be avoided, as well as other conditions such as steep sided valleys where exceptionally high wind speeds are found. c) Tie beams should be constructed to reduce the untied height of the columns to a maximum of 3 meters as shown in Figure 5. It is advisable to seek professional assistance for such construction, unless otherwise designed for larger columns.
4.1.8.2.2
Timber buildings
a) Because of the relatively light nature of a timber building, extra precautions shall be taken to prevent uplift. Care must therefore be taken to ensure that the entire structure is securely fastened to the foundations. b) The spaces between the supporting columns or piers may be filled in to reduce the uplift forces (see Figure 6). c) As far as timber walls are concerned, in addition to bracing corners in both directions, diagonal braces or steel straps must be installed at the level of the top plate to provide rigidity of the corners at that level (see Figures 7 and 8).
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 30/179
width of wall
50mm min
Section through concrete capping
roof level
roof reinforced concrete ring beam
frame of building floor level
Fig 4 - Typical roof gable wall arrangement
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 31/179
Roof level
Reinforced concrete ring beam
Frame of building Floor level
200x300 r.c. tie beam
200mm thk. r.c. blockwall
Existing grade
r.c. strip footing 600 mm min
Ground slopes should be less than 15 degrees
Roof level
Reinforced concrete ring beam
frame of building
200x300 r.c. tie beam 300x300 mm min r.c. column
existing grade r.c. footing
3 000mm maximum
Floor level
Steep slopes more than 15 degrees
Note: Those sketches don't show the shear panels
r.c. footing
900 mm min
and less than 30 degrees
Fig 5 - Recommended method of construction on sloping sites
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 32/179
Grade
100 X 100 Timber sill
r.c. tie beam
150 mm thick blockwork
Colomn may be 200 x 200mm reinforced concrete or block work filled with concrete and 4 - 12mm bars 8mm links - 200mm centers
Fig 6 - In-fill panel between timber building supports
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 33/179
Horizontal bracing for corners at wall plate level
Wall plate
Uprights
Sheating
Wall sill
Brace corners by diagonal bracings
Fig 7 - Timber framing showing bracing
Wall plate must be fastened and strapped to the top of uprights
Window opening Double uprights at openings Door opening
Wall sill is fixed to foundation wall by anchor bolts Wall sill
The uprights are fixed to the wall sill
Fig 8 - Timber framing for wall
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 34/179
roof sheeting
roof battens 50 x 150 timber rafter at 600mm centers ceiling material
metal hurricane tie every other rafter
200
timber wall plate
r.c. ring beam
roof eave 900mm (max) fascia board
150
100mm min
Fig 9 - Rafter/wall plate connections
50 x 100 timber wall plate
12mm anchor bolt at 1200mm centers (maximum) r.c. ring beam T 6mm stirrups @ 200 cts
Fig 10 - Rafter/ ring beam connections
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 35/179
metal hurricane tie imbedded in ring beam
Timber rafter
Infill concrete Timber wall plate r.c. ring beam
metal hurricane tie
Timber wall plate
Timber wall plate
Mortise
Tenon Metal strap
Timber upright
Timber upright
Fig 11 - Wall plate connections and hurricane ties
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.1.8.2.3
First edition Page 36/179
Steel buildings
The principles for the design and construction of hurricane resistant steel buildings are: a) Ensure that there are adequate numbers and sizes of foundation holding down bolts, and that they are all in place and properly fixed. b) Ensure that there is adequate lateral support provided by cross bracing or horizontal ties or by cast in place concrete or masonry walls. c) Where concrete walls or concrete masonry is used, the connections between the steel frames and the walls shall be provided. d) Ensure that the fabricator's recommendations with regards to the construction of the roof and roof covering are followed.
4.1.9
Roofs
4.1.9.1 Roofs with pitch between 0 and 20° (or a slope between 0 % and 36 %) are more vulnerable to uplift forces. It is recommended that roofs be constructed with a pitch between 20° and 40° (or a slope between 36 % and 84 %). 4.1.9.2 The aptitude to reduce uplift forces is affected by the shape of the roof in the following order from the most effective to the least effective:
a) Hip roof b) Gable c) Shed 4.1.9.3 Attention should be given to the location of fixings used for the roof cladding. It is necessary to provide additional fixings at the roof edges and ridge, since high-localised pressures are produced in these locations. 4.1.9.4 Roof overhangs also experience high local pressures and, where possible, these should be kept to a minimum or adequately strengthened. 4.1.9.5 Where buildings have covered patios or verandas, their roofs may be separate structures rather than extensions of the main building roof. A patio or veranda roof may be lost without endangering the safety of the main roof. 4.1.9.6 The main roof must be securely fixed to the ring beam and ridge beams and details for achieving this are shown in Figures 9, and 10 and 11.
4.1.10
Windows and doors
Special attention must be paid to the installation of doors and windows, since the loss of a door or window during a hurricane will greatly alter the internal pressure of the building, thus adversely affecting its safety. For this reason, glazed windows and doors may be fitted with shutters.
File # Small building code 2004_draft
Date 01 July, 2004
File # Small building code 2004_draft
Shear panel
Masonry Ground floor slab suspended or on grade
Masonry Suspended ground floor slab with crawl space
Masonry Suspended first floor slab Ground floor slab suspended or on grade
Columns, beams & shear panel structure Ground floor slab suspended or on grade
Columns, beams & shear panel structure Suspended ground floor slab with crawl space
Columns, beams & shear panel structure Suspended first floor slab Ground floor slab suspended or on grade
Framed structure Ground floor slab suspended or on grade
Framed structure Suspended ground floor slab with crawl space
Framed structure Suspended first floor slab Ground floor slab suspended or on grade
Trinidad & Tobago Small Building Code First edition Page 37/179
Fig 12 - Basic 1 or 2 level house type
Date 01 July, 2004
File # Small building code 2004_draft
Fig 13 - Mixed 1 or 2 level house type
Date 01 July, 2004 First level masonry Crawl space framed structure Suspended ground floor slab
First level masonry Ground level framed structure Suspended first floor slab Ground floor slab suspended or slab on grade
Sloping site
First level masonry Crawl space columns, beams & shear panel structure Suspended ground floor slab
First level masonry Ground level columns, beams & shear panel structure Suspended first floor slab Ground floor slab suspended or slab on grade
Flat site 2 levels
Trinidad & Tobago Small Building Code First edition Page 38/179
File # Small building code 2004_draft
Fig 14 - 1 or 2 level house, other combination
Date 01 July, 2004
One level timber Ground floor slab suspended or on grade
First level timber Suspended ground floor slab with crawl space
First level timber Suspended first floor slab Ground floor slab suspended or on grade
Shear panel
First level cold formed steel Crawl space columns, beams & shear panel structure Suspended ground floor slab
First level timber Ground level columns, beams & shear panel structure Suspended first floor slab
First level metallic structure Crawl space framed structure Suspended ground floor slab
First level timber Ground level framed structure Suspended first floor slab
Trinidad & Tobago Small Building Code First edition Page 39/179
Trinidad & Tobago Small Building Code
4.2
First edition Page 40/179
Design criteria
4.2.1
Conventional design
--- Buildings and structures, and all parts thereof, shall be constructed to support safely all loads, including dead loads. --- Where different construction methods and structural materials are used for various portions of a building, the applicable requirements of this part for each portion shall apply. 4.2.1.1
Conventional building
--- Conventional construction shall be considered as building with acceptable shape of the Figures 12, 13 and 14, “1 and 2 level house type”. --- All conventional construction shall be designed in accordance with this code. 4.2.1.2
Irregular building
--- Irregular buildings shall have an engineered lateral-force resisting system designed in accordance with accepted engineering practice. --- A building shall be considered to be irregular when one or more of the following conditions occur:
a) When exterior shear panels or reinforced frame is not in one plane vertically from the foundation to the uppermost story in which they are required. (See Framed structure) b) When a section of floor or roof is not laterally supported by shear panel or reinforced frame on all edges. c) When an opening in a floor or roof exceeds the lesser of 3.60m or 50% of the least floors or roofs dimension. d) When portions of a floor level are vertically offset. e) When shear panel or reinforced frame is do not occur in two perpendicular directions. f)
When shear panel or reinforced frame are constructed of dissimilar bracing systems on any one-story level above grade. --- Limit of this code:
When a building of otherwise conventional construction contains structural elements, which exceed the limits of this code, those elements shall be designed in accordance with accepted engineering practice.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.2.2 4.2.2.1
First edition Page 41/179
Engineered design General
Buildings shall be constructed in accordance with the provisions of this code as limited by the provisions of this section. 4.2.2.2
Wind design.
The requirements in this document are based on design wind speed over open water at equivalent elevation of 10m average over 10 minutes with a recurrence of one in 50 years. 4.2.2.2.1
Minimum load Table 1 - Design pressure for winds
Design pressure
4.2.2.2.2
Trinidad
Tobago
Wind zone (Consensus conference)
Zone 2
Zone 3
Wall (horizontal load) kN/m²
0.80
1.00
Roof (minimum uplift) kN/m²
1.00
1.45
Site effect
--- The pressure above shall be modified to take in consideration the site effect in 3 categories. Site types
Protected
Normal
Exposed
Coefficients
0.80
1
1.35
--- It is considered as exposed , costal site until 5km from the sea or top of hill or ridge, E W valley and special site well now for this exposure. --- It is considered as protected area small building in down town or in special valley N S (This coefficient must be used with caution and the help of the Engineer). 4.2.2.3
Seismic design
All buildings shall be constructed in accordance with the provisions of this section. Seismic design category: 4.2.2.3.1 Ground acceleration
The requirements in this document are based on maximum ground acceleration associated with 10% probability of occurrence in 50 years. Trinidad and Tobago in Zone 3 (Consensus conference). for Trinidad
0.3 g
for Tobago
0.3 g 2
(g refers to the gravity and g = 9.81m/s ) a)
Amplification factor
Where the soil is 100% saturated (low land, reclaimed land, etc.) an amplification factor of 2 shall be applied to the ground acceleration. See calculation for shear load.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code b)
First edition Page 42/179
Soil liquefaction
To prevent any soil liquefaction on the same type of land than above a special attention shall be carried out with an engineer specialist for the choice of the appropriate type of foundation. See calculation for shear load.
4.2.2.3.2
Weights of applied finishes
--- Dead load finishes shall not exceed 1 kN/m2 for roofs or 0.5 kN/m2 for floors. --- Dead load finishes for walls above grade shall not exceed:
a - light-frame walls
0.75 kN/m2 for exterior 0.50 kN/m2 for interior
b - masonry walls
2.50 kN/m2 for 150mm thick masonry wall 3.80 kN/m2 for 200 mm thick masonry wall
c - concrete walls
4.2.2.3.3
4.10 kN/m2 for 150 mm thick concrete walls
Height limitations
The design applied to any construction is limited to two stories with a maximum of 9m to the top of the building.
4.2.2.4
Flood plain construction
Buildings and structures constructed in flood prone areas as established in Fig. 15 & 16 shall be designed and constructed in accordance with Clause - Flood resistant construction and Clause - Coastal high hazard areas of Part "Minimal requirements".
4.2.3
Dead load
The actual weights of materials and construction shall be used for determining dead load with consideration for the dead load of fixed service equipment.
4.2.4
Live load
The minimum uniformly distributed live load shall be as provided in Table 2. Table 2 - Minimum uniformly distributed live loads Use
Live loads (kN/m2) 1.5
Domestic floor - All rooms excepted above
2.5
Office floor – excepted above Small industrial and storage
5
Exterior and interior balconies, Corridors & Stairs
5
Use
Guard rails and handrails
File # Small building code 2004_draft
Horizontal loads (kN/m) 1
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 43/179
Fig A2-3 Trinidad flood prone areas
SWAMP HIGH OCCASIONAL SLIGHT UNLIKELY
Fig 15 – Trinidad flood prone area
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 44/179 N W
TOBAGO
E S
# P ly m o u th T u r tle B e a c h Bu cco o # S to r e Bay
##
P a r is h e s
#
Sc a rb o ro ug h
#
L o w la n d s
20
Coastal/Tidal
L o u is D 'o r # R o x b o ro ug h A r g y le
#
0
20
Area
Impact / Recurrence interval
Tobago north side
Buccoo 9m of limestone cliff eroded
Tobago south side
Roxborough
Tobago south side
Argyle
Tobago north side
Plymouth
Tobago north side
Turtle Beach Grange Bay
Tobago north side
Store Bay
Tobago north side
Pigeon Point
Fig 16 - Tobago flood prone areas
File # Small building code 2004_draft
Date 01 July, 2004
4 0 M i le s
Cause Flora 1953 1999 band
H.
Lenny
feeder
Trinidad & Tobago Small Building Code
4.2.5
First edition Page 45/179
Roof load.
Roof shall be designed for the live load indicated in Table 3. Table 3 - Minimum roof live loads (kN/m2)
Tributary loaded area for any structural members Roof slope
Area (m2) 0 to 20m2
Flat or rise less than (20°) 36% slope
20 to 55m2
over 55m2
1
0.75
0.6
Rise (20°) 36% to (45°) 100%
0.75
0.7
0.6
Rise greater than (45°) 100%
0.6
0.6
0.6
4.2.6
Lateral load design
4.2.6.1
Preamble
--- Wind and earthquake introduce horizontal loads in the superstructure that are transferred to the foundation. We have to consider 2 steps:
a) Transfer of the horizontal load from: i.
wind to vertical wall and roof.
ii. acceleration of mass located everywhere in the superstructure to the appropriated wall or framed structure. b) Transfer of the load from the top to the bottom of the wall or superstructure and the foundation. --- According to this code:
a)
horizontal transfer is done by horizontal diaphragm or horizontal beam and slab.
b)
vertical transfer is one by shear panel, cross, or framed structure.
4.2.6.2
Diaphragm
--- Floor, roof or ceiling assemblies may be constructed with the necessary stiffness and load path continuity to distribute lateral loads (wind and earthquake) to lateral support subsystems. In this role, floor, roof or ceiling surface act as horizontal beams (also called a diaphragm) spanning lateral supports points. --- Use of floor, roof or ceiling assembly, as a diaphragm requires both strength and stiffness properties and development of connections to transfer the diaphragm force. This consideration is very important to complete the role and action of the shear panel.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 46/179
Shear panel in 2 parts
Part elevation
ground level
Minimum L1=1000
L2 = 2400 - L1
In situ concrete
400
5 diam. 12
1 000
1 600
Shear panel in one part
ground level
Part elevation
400
In situ concrete
150mm min
1 800
Part plan In situ concrete 2 diam. 12 every 2 rows
Fig 17 - Shear panel - Vertical core blocks
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 47/179
Shear panel in two parts
ground level
Ring beam concrete and reinforcement
ground level
Part elevation
Part elevation L2 = 2400 mm - L1
L1 = 1000 min
Shear panel in one part 500
Ring beam concrete and reinforcement
Limit of opening location
4 dia. 12mm ground level
Part elevation
250mm min 150 min
1 800
200 115
2100 min
1600 max
6mm stirrup each 150mm
In situ concrete
m min
Part plan
Fig 18 - Shear panel - Horizontal core blocks
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.2.6.3
First edition Page 48/179
Shear panel
4.2.6.3.1
Concrete shear panel in wall
A shear panel (see Figures 17 and 18 - Shear panel) is a portion or section of a 150mm exterior wall that performs the function of resisting lateral earthquake or wind forces. 4.2.6.3.2
Timber
See Section - Wall bracing.
4.2.7
Load factors
All structures shall resist combined loads as follows:
4.2.7.1
Gravity
1.40 D + 1.70 L 4.2.7.2
Earthquake
a) 0.75 (1.40 D + 1.70 L +/- 1.87 E) and b) 0.90 D +/- 1.43 E
4.2.7.2.1
Shear load calculation
--- A simplified formula, for this code is: V = 0.05 x S x W x A
total shear in kN
--- Whereas:
The 0.05 coefficient integrated the Z = ground acceleration, C = amplification factor due to structure frequency, I = importance factor = 1 in this code and Rw = ductility factor related with respect to the column design reinforcement used in the normal practice formula. S = site factor
S=1
for good soil (rock, gravel)
S = 1.2 for softer material (clay, fill) S = 1.5 for deep alluvial deposits S = 2.5 maximum for reclaimed land and saturated soils (due to the amplification factor) W = total load in kN A = amplification factor
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.2.7.3
First edition Page 49/179
Wind
1.40 D + 1.70 L + 1.75 W Note : D = dead load L = live load E = earthquake load W = wind load
4.2.8
Deflection
The allowed deflection of any structural member under the live load shall not exceed the following values in Table 4. Table 4 – Maximum deflection authorised.
Floor slab, structural beam and ceilings
L/360
All others structural members
L/240
Rafters and purlins
L/180
Interior walls and partitions
H/180
Notes: L = span length H = span height
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.3
First edition Page 50/179
Minimal requirements
4.3.1 4.3.1.1
Site address Premises identification
Approved numbers or addresses shall be provided for all new buildings in such a position as to be plainly visible and legible from the street or road fronting the property.
4.3.2 4.3.2.1
Light Habitable rooms
All habitable rooms shall be provided with an area to allow natural light to enter not less than 10 percent of the floor area of such rooms. 4.3.2.2
Adjoining rooms
For purpose of determining requirements of light, any room shall be considered as a portion of an adjoining room when at least one-half of the area of the common wall is open and unobstructed and provides an opening of not less than 10% of the floor area of the interior room but not less than 2.50m2. 4.3.2.3
Bathrooms
Bathrooms, water closet compartments and other similar rooms shall be provided with an area to allow natural light to enter not less than 0.25m2. 4.3.2.4
Stairway illumination
--- All interior and exterior stairways shall be provided with a means to illuminate the stairs, including the landings and treads. --- Interior stairs shall be provided with an artificial light source located in the immediate vicinity of each landing at the top and bottom of the stairs. --- Exterior stairs shall be provided with an artificial light source located in the immediate vicinity of the top landing of the stairs. --- For commercial building, emergency lighting shall be provided for power failure conditions.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.3.3 4.3.3.1
First edition Page 51/179
Ventilation Natural ventilation
4.3.3.1.1
Habitable rooms
--- Natural ventilation shall be provided in all habitable room through windows, louvers or other natural openings through the external wall to the outdoor air. --- The minimum area of ventilation shall be not less than 15% of the floor area of such rooms, of which of 5% shall be fix ventilation. 4.3.3.1.2
Adjoining rooms
For purpose of determining ventilation requirements, any room shall be considered as a portion of an adjoining room when at least one-half of the area of the common wall is open and unobstructed and provides an opening of not less than 15% of the floor area of the interior room but not less than 2.50m2. 4.3.3.1.3
Bathrooms
Bathrooms, water closet compartments and other similar rooms shall be provided with a ventilation area not less than 0.25m2. 4.3.3.2
Mechanical ventilation
4.3.3.2.1
Principle
--- The centralised ventilation system ensures air renewal to keep the occupants healthy and to protect the building from being damaged by the moisture. A quiet and continuous ventilation of the house is provides an incomparable indoor air quality to the house. --- The system consists of a central extract unit connected to the exhaust grilles by spiral ductwork. Fresh air is introduced into bedroom and lounge through self balancing inlets. Fresh air inlets are fitted either straight across the wall or as trickle vents. Stale air is extracted into the high moisture producing rooms (kitchen, bathrooms and toilets) through self balancing exhaust outlets. --- The centrifugal fan unit is located on the roof or in the loft space and is connected to galvanised metal ducting to outside.
Fig 19 - Mechanical ventilation - Principle
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.3.3.2.2
First edition Page 52/179
Habitable rooms
--- All habitable rooms shall be provided with the minimum ventilation rates of 30m3/hr for continuous ventilation for every 12m2 of the floor area or part of such rooms. --- This ventilation shall be through windows, doors or other natural openings through the external wall from the outdoor air through a special 30m3/hr-air regulator. 4.3.3.2.3
Kitchen and bathrooms
--- All the air introduced into the house through the habitable rooms (e.g. Living, dining, bedroom, corridor and entrance) shall be extracted in the rooms e.g. kitchen, bathroom, toilet, washing room and other similar rooms have to be maintained in depression to create an air flow through the house. --- The minimum exhaust airflow for each room is as follows: Kitchen
120 m3/hr
Bathroom
60 m3/hr
Shower
60 m3/hr
Toilet (WC)
30 m3/hr
Washing room and store room
30 m /hr
3
--- This ventilation air shall be exhausted permanently and directly outside. 4.3.3.2.4
Internal doors
All internal doors have to be provided with air passages not less than 150 cm2. Note: These passages can be provided with a bottom gap of 20 or 25mm under the door. 4.3.3.2.5
Minimum global ventilation
For each house or apartment the minimum ventilation rate is one volume per hour of the habitable part of the house.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.3.4
4.3.4.1
First edition Page 53/179
Minimum room sizes
Habitable rooms
--- Every dwelling unit shall have at least one habitable room (living or sleeping room), which shall be not less than 12m2 of floor area. --- Other habitable rooms shall have a gross area of not less than 7.50m2. 4.3.4.2
Other rooms
Kitchen
not less than 5m2
Bathroom
not less than 3m2and not less than 2m2 for the second one
Shower
not less than 1.5m2
Toilet (WC)
not less than 1m²
WC for handicapped people the minimum area must be3m² See Figures: 20 - Minimum room sizes, 21 - Typical furniture arrangement and 22 - Typical arrangement 7.5m2 room.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 54/179
900mm min
1400mm min
1800mm min 1732mm square
2236mm 1667mm 2143mm 1732mm
2778mm 2236mm
Kitchen 5m2 min
Shower 1.5m2 min
Bath. 3m2 min
750mm min
1333mm
800mm
WC 1m2 min
2500mm minimum
3000mm
3464mm square
2500mm minimum 2739mm square
4800mm
4000mm 3464mm
Main room 12m2 min
Other room 7.5m2 min
3000mm 2739mm
Fig 20 - Minimum room sizes
File # Small building code 2004_draft
Date 01 July, 2004
1250mm min
Trinidad & Tobago Small Building Code
First edition Page 55/179
1800mm min
1400mm min
Bathroom 3m2 min 2143mm 2778mm
Kitchen 5m2 min
685mm
785mm
900mm mini
890mm
Entrance
Shower 1.5m2 min 1667mm
3000mm 685mm
750mm min
4000mm
Main room 12m2 min 1333mm
WC 1m2 min 685mm
Fig 21 - Typical furniture arrangement (except for handicapped)
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 56/179
Other room 7.5m2 min
2500mm minimum
3000mm
2500mm minimum
3000mm
Fig 22 - Typical furniture arrangement - 7.5 m2 room
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.3.4.3
First edition Page 57/179
Minimum dimensions
Habitable rooms shall not be less than 2.50m in any horizontal dimension. Other rooms
minimum
Kitchen
1.80m wide.
Bathroom
1.40m wide.
Shower
0.90m wide.
Toilet (WC)
0.75m wide and 1.25m long.
Corridor
1.00m wide.
Stair
1.00m wide.
4.3.4.4
Height effect on room area
Portions of a room with a sloping ceiling measuring less than 1.50m or a furred ceiling measuring less than 2.15m from the finished floor to the finished ceiling shall not be considered as contributing to the minimum required habitable area for that room. 4.3.5
4.3.5.1
Ceiling height
Minimum height
4.3.5.1.1
Habitable rooms
Habitable rooms (living or sleeping room) shall have a ceiling height of not less than 2.40m. See Figure 23 - Habitable room area 4.3.5.1.2
Other rooms
Other rooms e.g. corridors, bathrooms, toilet rooms, utility room, storage and laundry etc shall have a ceiling height of not less than 2.15m. 4.3.5.1.3
Measurement
The required height shall be measured from the finish floor to the lowest projection from the ceiling. 4.3.6
Minimum passage
The minimum passage for the access to the dwelling and each room shall be as follows: 4.3.6.1
Main entrance
At least one access door from outside shall be not less than 900mm wide and 2000mm high. 4.3.6.2
Habitable rooms and secondary rooms, e.g. store and laundry
All passage for access from another room or from the corridor shall be not less than 785mm wide and 2000mm high (except for handicapped people 900mm wide).
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code 4.3.6.3
First edition Page 58/179
Other rooms e.g. Bathroom and toilet
All passage for access from another room or from the corridor shall be not less than 685mm wide and 2000mm high (except for handicapped people 900mm wide).
Room total area Habitable area
2.40m area
Nota: 2.40m area >= 80% of habitable area
2400mm
2150mm lowest habitable part 1500mm m
Fig 23 - Habitable room area
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code
4.3.7
First edition Page 59/179
Sanitation
4.3.7.1
Toilet facilities
--- Every dwelling unit shall be provided with a water closet or privy, lavatory basin, and a bathtub or shower. --- Toilet access shall be not from kitchen or dining area. 4.3.7.2
Kitchen
--- Each dwelling unit shall be provided with a kitchen area and every kitchen area shall be provided with adequate waste disposal system (e.g. sink). --- In small commercial enterprise approval for this kitchen designs must be given by the Public Health Inspectorate. 4.3.7.3
Sewage disposal
All plumbing fixtures shall be connected to a sanitary sewer or to an approved private sewage disposal system. Approval shall be granted by WASA or other agency authorised to do so on their behalf. 4.3.7.3.1
Septic tank for single family house Table 5 – Size ratio for septic tanks
Capacity Ratio per person/full time user 5 persons 8 persons
All wastes 500 litres/p 2500 litres 4000 litres
--- The capacity of the septic tank shall be calculated on the basis of the ratio above and the minimum capacity is 2,500 litres. --- The water table must be a minimum of 1 metre deeper than the septic tank. See Figures 25 for 2500 litres and 26 for 4000 litres septic tank. See also "Code of Practice for the Design and Construction of Septic Tanks and Associated Secondary Treatment and Disposal System" TTS 16 80 400: 1991 or the latest version. Note: The above figures complied with this code. 4.3.7.3.2
Soak-away pit for single family house
See Figure 27 --- The water table must be a minimum of 1 metre deeper than the soak-away base. 4.3.7.3.3
Draining trench for single family house
Where is impossible to make a soak-away, a draining trench shall be used See Figure 28 4.3.7.4
Water supply to fixtures
--- All plumbing fixtures shall be connected to an approved water supply. Approval shall be granted by WASA or other agency authorised to do so on their behalf. --- Kitchen sinks, lavatory basins, bathtubs, showers, bidets, laundry tubs and washing machine outlets shall be connected to the water supply system. 4.3.8 4.3.8.1
Toilet, bath and shower spaces Space required
Fixtures shall be spaced as per Figure 24 - Toilet, bath and shower spaces required.
File # Small building code 2004_draft
Date 01 July, 2004
Trinidad & Tobago Small Building Code 4.3.8.2
First edition Page 60/179
Bathtub and shower spaces
Bathtub and shower floors and walls shall be finished with a smooth, hard and non-absorbent surface. Such wall surfaces shall extend to a height of not less than 1.80m above the floor.
min 375mm
min 100mm
min 100mm
min 100mm
clearance mini. 600mm
Lavatories min 50mm
Wall
Tub Shower
min 900mm
900mm min
Clearance in front of opening 600mm min min 300mm
min 375mm
Tub Clearance min 600mm
Tub
Water closet or bidet
Fig 24 - Toilet, bath and shower space required (except handicapped)
File # Small building code 2004_draft
Date 01 July, 2004
Recommended cover
File # Small building code 2004_draft 900
Fig 25 - Septic tank 2500 litres - 5 persons max
Date 01 July, 2004 1500 1500mm min from building or boundary
900
906
All concrete blocks filled with concrete min 150mm thick
900
2365
1210
2060
45°
dia 12mm every 200mm both directions
408
100
400 concrete
1600
1500
950
1462
Outlet
Tie beam
1192
4 dia 12x 2000mm every 2 rows and tie beam
900
inside waterproof liner
500
50
dia 12mm every 200mm
8 dia 10mm
590
100
Sewage inlet min slope 2% (1 in 50)
min 400mm 6 dia 10mm
Cleanout 100mm
Ventilation pipe 100mm
Trinidad & Tobago Small Building Code First edition Page 61/179
2150 150
File # Small building code 2004_draft
Fig 26 - Septic tank 4000 litres - 8 persons max
Date 01 July, 2004 1500
2600
1500mm min from building or boundary
1300
1300
1604
All concrete blocks filled with concrete min 150mm thick
1604
2295
408 dia 12mm every 200mm both directions
concrete
1600
1500
900 100
950
400
550
1657
Outlet
Tie beam
1192
4 dia 12x 2500mm every 2 rows and tie beam
950
900
inside waterproof liner
550
50
dia 12mm every 200mm
8 dia 12mm
520
100
Sewage inlet min slope 2% (1 in 50)
mjn 400mm 6 dia 10mm
Cleanout 100mm
Ventilation pipe 100mm
Recommended cover
Trinidad & Tobago Small Building Code First edition Page 62/179
2150 150
45°
Trinidad & Tobago Small Building Code
First edition Page 63/179
min 2500mm from face of building
min 1000mm to boundary
Concrete slab 1700 square min
Top soil and vegetation 100
dia. 1400mm
25mm stone
800
Natural sand vein (porous layer)
800
2500mm minimum
50mm flat stone
1100
Fig 27 - Soak-away
File # Small building code 2004_draft
900
Inlet
Date 01 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 64/179
min 2500mm /building
min 1000/boundary Perforated 100mm pipe
400
650
Inlet
1200
general slope 2% (1 in 50)
150
Top soil and vegetation
Natural sand vein
500
25mm stone 10 metres minimum
Fig 28 - Draining trench
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.3.9 4.3.9.1
First edition Page 65/179
Glazing Identification
Each pane of glazing installed in hazardous locations shall be provided with a manufacturers or installers label, designating the type and thickness of glass and the safety glazing standard with which it complies, which is visible in the final installation. The label shall be acid etched, sandblasted, ceramic-fired, embossed mark, or shall be of a type, which once applied cannot be removed without being destroyed. 4.3.9.1.1
Identification of multi-pane assemblies
Multi-pane assemblies having individual panes not exceeding 0.10m2 in exposed area shall have at least one pane in the assembly identified. All other panes in the assembly shall be labelled. 4.3.9.2
Louvered windows or jalousies
Regular, float, wired or patterned glass in jalousies and louvered windows shall be no thinner than nominal 4.80mm and no longer than 1.20m. Exposed glass edges shall be smooth. 4.3.9.2.1
Wired glass prohibited
Wired glass with wire exposed on longitudinal edges shall not be used in jalousies or louvered windows. 4.3.9.3
Human impact loads
Individual glazed areas including glass mirrors in hazardous locations such as those indicated shall pass the test requirements of CPSC 16-CFR, Part 1201. 4.3.9.4
Hazardous locations
--- The following shall be considered specific hazardous locations for the purposes of glazing: 1.Glazing in ingress and means of egress doors except jalousies. 2.Glazing in fixed and sliding panels of sliding (patio) door assemblies and panels in doors including walk-in closets. 3.Glazing in storm doors. 4.Glazing in all unframed swinging doors. 5.Glazing in doors and enclosures for hot tubs, whirlpools, saunas, steam rooms, bathtubs and showers. Glazing in any part of a building wall enclosing these compartments where the bottom exposed edge of the glazing is less than 1.50m measured vertically above any standing or walking surface. 6.Glazing, in an individual fixed or operable panel adjacent to a door where the nearest vertical edge is within a 600mm arc of the door in a closed position and whose bottom edge is less than 1.50m above the floor or walking surface. 7.Glazing in an individual fixed or operable panel, other than those locations described in Items 5 and 6 above, that meets all of the following conditions: 7.1 Exposed area of an individual pane greater than 0.80m2. 7.2 Bottom edge less than 450mm above the floor. 7.3 Top edge greater than 900mm above the floor. 7.4 One or more walking surfaces within 900mm horizontally of the glazing. 8. All glazing in railings regardless of an area or height above a walking surface. Included are structural baluster panels and non-structural in-fill panels. 9. Glazing in walls and fences enclosing indoor and outdoor swimming pools where the bottom edge of the poolside is (1) less than 1.50m above a walking surface and (2) within 1.50m horizontally of the water’s edge. This shall apply to single glazing and all panes in multiple glazing. --- Special solution my be required and not cover in this document.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code 4.3.9.5
First edition Page 66/179
Wind and dead loads on glass
4.3.9.5.1
Vertical glass
All glass sloped 15 degrees or less from vertical in windows, window walls, doors and other exterior applications shall be designed to resist the wind loads specified in Clause 4.2 - Design criteria, Table 1 - Design pressure for winds. Glazing designed in accordance with these provisions shall be firmly supported on all four edges. 4.3.9.5.2
Sloped glazing
All glass sloped more than 15 degrees from vertical in skylights, sunspaces, sloped roofs and other exterior applications shall be designed to resist the most critical combinations of loads. 4.3.9.5.3
Thicker glass
Allowable loads for glass thicker than 6.4 mm shall be determined in accordance with ASTM E 1300. 4.3.9.6
Skylights and sloped glazing
4.3.9.6.1
Definition
Any installation of glass or other transparent or translucent glazing material installed at a slope of 15 degrees or more from vertical. Glazing materials in skylights, solariums, sunspaces, roofs and sloped walls are included in this definition. 4.3.9.6.2
Permitted materials
The following types of glazing may be used: 1. Laminated glass with a minimum 0.40mm poly-vinyl-butyral interlayer for glass panes 1.50m2 or less in area located such that the highest point of the glass is not more than 3.60m above a walking surface or other accessible area; for higher or larger sizes, the minimum interlayer thickness shall be 0.80mm. 2. Fully tempered glass. 3. Heat-strengthened glass. 4. Wired glass. 5. Approved rigid plastics. 4.3.9.6.3
Screens general
For fully tempered or heat-strengthened glass, a retaining screen shall be installed below the glass, except for fully tempered glass. 4.3.9.6.4
Screens with multiple glazing
When the inboard pane is fully tempered, heat-strengthened, or wired glass, a retaining screen shall be installed below the glass. 4.3.9.6.5
Screens not required
Screens shall not be required when fully tempered glass is used as single glazing or the bottom pane in multiple glazing and either of the following conditions is met: 1. Glass area 1.50m2 or less. Highest point of glass not more than 3.60m above a walking surface or other accessible area, nominal glass thickness not more than 4.80mm, and (for multiple glazing only) the other pane or panes fully tempered, laminated or wired glass. 2. Glass area greater than 1.50m2. Glass sloped 30 degrees or less from vertical and highest point of glass not more than 3.00m above a walking surface or other accessible area.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code 4.3.9.6.6
First edition Page 67/179
Screen characteristics
The screen and its fastenings shall: 1 - be capable of supporting twice the weight of the glazing. 2 - be firmly and substantially fastened to the framing members, and 3 - have a mesh opening of no more than 25 mm by 25 mm. 4.3.9.6.7
Curbs for skylights
All unit skylights installed in a roof with a pitch flatter than 25 percent slope shall be mounted on a curb extending at least 100mm above the plane of the roof unless otherwise specified in the manufacturer’s installation instructions.
4.3.10
Enclosed car ports
4.3.10.1
---
Opening protection
Openings from a private carport into a room used for sleeping purposes shall not be permitted.
--- Other openings between the carport and residence shall be equipped with either solid wood doors not less than 35 mm in thickness or 30-minute fire-rated doors. 4.3.10.1.1 Duct penetration
Ducts penetrating and installed in the walls or ceilings separating the dwelling from the carport shall be constructed of a minimum 0.50mm sheet steel and shall have no openings into the garage. 4.3.10.2
Separation required
Enclosed carport shall be separated from the residence with 30 min. fire rated wall and/or slab. 4.3.10.3
Floor surface
--- Garage and carport floor surfaces shall be of approved non-combustible material. --- The area of floor used for parking of automobiles or other vehicles shall be sloped to facilitate the movement of liquids to a drain or toward the main vehicle entry doorway. 4.3.11 4.3.11.1
Emergency escape and rescue openings Emergency escape and rescue required
--- Basements with habitable space and every sleeping room shall have at least one openable emergency escape and rescue window or exterior door opening for emergency escape and rescue. --- Where openings are provided as a means of escape and rescue they shall have a sill height of not more 1.10m above the floor. The net clear opening dimensions required by this section shall be obtained by the normal operation of the window or door opening from the inside. Escape and rescue window openings with a finished sill height below the adjacent ground elevation shall be provided with a window well. 4.3.11.1.1 Minimum opening area
All emergency escape and rescue openings shall have a minimum net clear opening of 0.50m2. 4.3.11.1.2 Minimum opening height
The minimum net clear opening height shall be 600mm. 4.3.11.1.3 Minimum opening width.
The minimum net clear opening width shall be 600mm.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.3.11.2
First edition Page 68/179
Window wells
The horizontal dimensions of a window well shall allow the emergency escape and rescue opening to be fully opened. The horizontal dimensions of the window well shall provide a minimum net clear area of 0.85m2 with a minimum horizontal projection and width of 900 mm. 4.3.11.2.1 Ladder and steps
--- Window wells with a vertical depth greater than 1.10m below the adjacent ground level shall be equipped with a permanently affixed ladder or steps usable with the window in the fully open position. --- Ladders or rungs shall have an inside width of at least 300mm, shall project at least 75mm from the wall and shall be spaced not more than 450mm on centre vertically for the full height of the window well. --- Architectural internal provision must be made for physically challenged. 4.3.11.3
Bars, grills, covers and screens
Bars, grills, covers, screens or other obstructions placed over emergency escape and rescue openings or window wells that serve such openings shall be releasable or removable from the inside without the use of a key, tool or special knowledge. 4.3.12 4.3.12.1
Exits Exit door required
--- Not less than one exit door conforming to this chapter shall be provided from each dwelling unit. The required exit door shall provide for direct access from the habitable portions of the dwelling to the exterior without requiring travel through a garage or kitchen. --- If the distance, measured centre of the corridor, between the house main entrance and the inside kitchen door is more than 6m a second exit is required directly in the kitchen. 4.3.12.2
Type of lock or latch.
All egress doors shall be readily openable from the side from which egress is to be made without the use of a key. 4.3.12.3
Type and Size
--- The required exit door shall be a side-hinged door that allow a clear opening not less than 900mm in width and 2025mm in height. --- Other exterior hinged or sliding doors shall not be required to comply with these minimum dimensions. 4.3.12.4
Hallways
The minimum width of a hallway or exit access shall be not less than 1m. 4.3.12.5
Exit facilities
Exterior exit balconies, stairs and similar exit facilities shall be positively anchored to the primary structure at not over 2.40m on centre or shall be designed for lateral forces. Such attachment shall not be accomplished by use of toenails or nails subject to withdrawal.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 69/179
minimum opening in slab 2m min
Top landing
2.15m min
12 risers maximum Intermediate landing
Minimum clearance
2m min
Floor to floor 2.15m min
12 risers maximum
Bottom landing
900mm min
900mm min
900mm min
1m mini
900mm min
900mm min
1m min
1m min
1m min
1m min
900mm min
900mm
1m min
900mm min
1m min
900mm
1m min
1m min
900mm 900mm
Fig 29 - Stairs and landings
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.3.13 4.3.13.1
First edition Page 70/179
Landings on stairways Landings required
There shall be a floor or landing at the top and bottom of each stairway. There shall be a floor or landing on each side of an exit door. 4.3.13.2
Size
See Figure 29 - Stairs and landings. The width of each landing shall not be less than the stairway or door served. Every landing shall have a minimum dimension of 900mm measured in the direction of travel. 4.3.13.3
Location
The floor or landing shall be not more than 35mm lower than the top of the threshold. 4.3.13.4
Landing required
A minimum 1m by 900mm landing shall be provided: 1. At the top and bottom of ramps, 2 . Where ramps changes direction, 3. After no more than 12 high steps (or change of direction as shown on Figure 29). 4. Where doors open onto stairway the minimum size shall be 1.5m by 900mm. 4.3.14
Pedestrian ramps
See Figure 30 - Ramps and landings 4.3.14.1
Maximum slope
Ramps shall have a maximum slope of 10 percent. 4.3.14.2
Handrails required
Handrails shall be provided on at least one side of all ramps. 4.3.14.3
Landing required
A minimum 1m by 1m landing shall be provided: 1. At the top and bottom of ramps, 2. Where ramps changes direction, 3. Where doors open onto ramps the minimum landing size shall be 1.5m by 900mm.
4.3.15 4.3.15.1
Stairways Width
Stairways shall not be less than 900mm in clear width at all point. 4.3.15.2
Treads and risers
--- The maximum riser height shall be 200mm and the minimum tread depth shall be 250mm. Rise and tread should respect the formula 600mm < 2xRise + Tread < 640mm. --- The riser height shall be measured vertically between leading edges of the adjacent treads. The tread depth shall be measured horizontally between the vertical planes of the foremost projection of adjacent treads and at a right angle to the tread’s leading edge.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 71/179
--- The walking surface of treads and landings of a stairway shall be sloped no steeper than 2 percent slope. --- The greatest riser height within any flight of stairs shall not exceed the smallest by more than 5 mm. The greatest tread depth within any flight of stairs shall not exceed the smallest by more than 10mm. --- The treads finishing should not be slippery. p Bottom landing
Maximum slope 10%
g
1m minimum
1m minimum
1m minimum
1m minimum
Bottom landing 1m minimum
Up
Top landing
1m minimum
1m minimum
Bottom landing
Up
1m minimum
Intermediate landing Top landing
Up
1m minimum
1m minimum
Bottom landing 1m minimum
1m minimum
Up
Intermediate landing
Up
Top landing
Fig 30 - Ramps and landings File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 72/179
tread depth 250mm min
R 10mm maximum
riser height 200mm max
250mm min
100mm max
200mm maximum
Open risers
Sloped risers
30° max
30° max
Min 20mm / Max 32mm R 10mm max
Nosing
Fig 31 - Steps (Treads, risers and nosing)
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 73/179
Section F 1m minimum 900mm minimum R mini = 5mm 2m min 32mm min/ 65mm max
Handrail
F
40mm minimum 1m (+/- 10mm)
One handrail
900mm minimum
32mm min / 65mm max 40mm minimum
40mm minimum
Two handrails
Fig 32 - Stair handrails
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 74/179
4.3.15.2.1 Profile
--- The radius of curvature at the leading edge of the tread shall be no greater than 10mm. See Figure 31 - Steps (Treads, risers and nosing). --- When nosing is provided, shall be not less that 20mm but not more than 32 mm on stairways with solid risers. Bevelling of nosing shall not exceed 10mm. --- Risers shall be vertical or sloped from the underside of the leading edge of the tread above at an angle not more than 30 degrees from the vertical. Open risers are permitted, provided that the opening between treads does not permit the passage of a 100mm sphere.
4.3.15.3
Headroom
The minimum headroom in all parts of the stairway shall not be less than 2.00m measured vertically from the sloped plane adjoining the tread nosing or from the floor surface of the landing or platform. See Figures 29 and 32. 4.3.15.4
Winders
--- Winders are permitted, provided that the depth of the tread at a point not more than 500mm from the side where the treads are narrower should be not less than the depth of tread of the other section. --- The continuous handrail required shall be located on the side where the tread is narrower.
4.3.15.5
Spiral stairs
--- Spiral stairways are permitted, provided the minimum width shall be 700mm with each tread having a 200mm minimum tread depth at 350mm from the narrow edge. All treads shall be identical, and the rise shall be no more than 240mm. Minimum headroom of 2.00m shall be provided. --- Spiral stairs are not to be considered as fire escapes.
4.3.15.6
Circular stairways
Circular stairways shall have a tread depth at a point not more than 350mm from the side where the treads are narrower of not less than 300mm and the minimum depth of any tread shall not be less than 150mm. Tread depth at any walking line, measured a consistent distance from a side of the stairway, shall be uniform.
4.3.15.7
Wooden stair protection
Any enclosed accessible space under stairs shall have walls, under stair surface and any soffits protected on the enclosed side with 13mm gypsum board.
4.3.15.8
Stair illumination
All stairs shall be provided with illumination in accordance with Electrical Code.
4.3.16 4.3.16.1
Handrails Handrails
Handrails having minimum heights of 1.00m measured vertically from the nosing of the treads shall be provided on at least one side of stairways. All required handrails shall be continuous for the full length of any stairs with three or
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 75/179
more risers. Ends shall be returned or shall terminate in newel posts or safety terminals. Handrails adjacent to a wall shall have a space of not less than 40mm between the wall and the handrail. See Figures 32 - Stair handrails and 33 - Guards.
Stair with string Stair without string
Ø100mm min
1m (+/- 10mm)
1m (+/- 10mm)
String
Ø100mm min
Not acceptable
Ø100mm min
1m minimum Ø100mm min Not acceptable
height more than 750mm
Fig 33 - Guards
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.3.16.2
First edition Page 76/179
Handrail grip size
The handgrip portion of handrails shall have a cross section of 32mm minimum to 65mm maximum. Other handrail shapes, which provide an equivalent grasping surface, are permissible. Edges shall have a minimum radius of 3mm. 4.3.17 4.3.17.1
Guards Guards required
Porches, balconies or raised floor surfaces located more than 750mm above the floor or grade below shall have guards not less than 1.00m in height. Open sides of stairs with a total rise of more than 750mm above the floor or grade below shall have guards not less than 1.00m in height measured vertically from the nosing of the treads. See Figure 33 – Guards. 4.3.17.2
Guard rail-opening limitations
Required guards on open sides of stairways, raised floor areas, balconies and porches shall have intermediate rails or ornamental closures which do not allow passage of a sphere 100mm or more in diameter. Required guards shall not be constructed with horizontal rails or other ornamental pattern that results in a ladder effect. 4.3.18
Smoke detectors
--- No requirement for smoke detector except: a) In all wooden house where smoke detector shall be installed in each bedroom, outside each separate sleeping area in the immediate vicinity of the bedrooms and on each additional storey of the dwelling, including basement. b)
In all two-storied (multi-storied) buildings with only one internal stairway.
--- Detectors are not required in crawl space and uninhabitable attics.
4.3.19 4.3.19.1
Foam plastic General
The provisions of this section shall state the requirements and uses of foam plastic as insulation, structural filling or decoration. 4.3.19.2
Foam characteristics
4.3.19.2.1 Internal characteristics
The minimum density shall be more than 3 kN/m3. 4.3.19.2.2 Surface burning characteristics
All foam plastic or foam plastic cores in manufactured assemblies used in building construction shall have a flamespread rating of not more than 75 and shall have a smoke-developed rating of not more than 450 when tested for the maximum thickness intended for use in accordance with ASTM E 84.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code 4.3.19.3
First edition Page 77/179
Foam protection
All foam shall be protected from inside and outside by appropriated barrier to prevent damage from: 1- Vapour (humidity from hot air migrating from the hot side to the cold side of the wall, in this region from outside to inside) 2- Fire (both sides) 3- Rodent (rats, mice, etc.) 4- Termites 4.3.19.3.1 Thermal barrier
Foam plastic shall be separated from the exterior of the building by minimum vapour barrier as follows: - Polythene 0.150 mm thick (included in the wall complex) - or metallic cladding (corrosion resistant sheet of 0.50 mm minimum) - or 25mm thickness of masonry or concrete. 4.3.19.3.2 Fire barrier
To allow a minimal ignition protection of 15minutes a fire barrier shall be used as follows: a)
From outside
- Metallic cladding (corrosion resistant sheet of 0.50 mm minimum) - or 25mm minimum thickness of masonry or concrete - or 20mm minimum of structural wood - or 25mm minimum particleboard. b)
From inside
- Metallic cladding - or 25mm minimum thickness of masonry or concrete - or 20mm minimum of structural wood - or 25mm minimum particle board. - or 13mm gypsum board (the gypsum board shall be installed using a mechanical fastening system to ensure that the gypsum board will remain in place when exposed to fire). 4.3.19.3.3 Rodent damage (rats, mice, etc.)
All foam shall be externally protected against any destruction by rodents. This applies to the edge of the foam. 4.3.19.3.4 Termite damage
The use of foam plastics in areas of termite infestation shall be in accordance with this code. 4.3.19.4
Specific requirements
4.3.19.4.1 Foam-filled doors
Foam-filled doors are exempt from the requirements of this Section.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 78/179
4.3.19.4.2 Interior trim
--- Foam plastic trim defined as picture moulds, chair rails, baseboards, handrails, ceiling beams, door trim and window trim may be installed, provided that: 1. The minimum density is 3.50kN/m3. 2. The maximum thickness of the trim is 13mm and the maximum width is 100mm. 3. The trim constitutes no more than 10 percent of the area of any wall or ceiling. 4. The flame-spread rating does not exceed 75 when tested per ASTM E 84. --- The smoke-developed rating is not limited.
4.3.20 4.3.20.1
Flame spread and smoke density Wall and ceiling
Wall and ceiling finishes shall have a flame-spread classification of not greater than 200. 4.3.20.2
Smoke developed index
Wall and ceiling finishes shall have a smoke developed index of not greater than 450. 4.3.20.3
Testing
Tests shall be made in accordance with ASTM E 84.
4.3.21 4.3.21.1
Insulation Insulation
Insulation materials, including facings, such as vapour barriers or breather papers installed within floor-ceiling assemblies, roof-ceiling assemblies, wall assemblies, crawl spaces and attics shall have a flame-spread index not to exceed 25 with an accompanying smoke developed index not to exceed 450 when tested in accordance with ASTM E 84. 4.3.21.2
Loose-fill insulation
Loose-fill insulation materials, which cannot be, mounted in the ASTM E 84 apparatus without a screen or artificial supports shall have a flame-spread rating not to exceed 25 with an accompanying smoke-developed factor not to exceed 450 when tested in accordance with CAN/ULC-SI02-M88. 4.3.21.3
Cellulose loose-fill insulation
Cellulose loose-fill insulation shall comply with CPSC 16-CFR, Parts 1209 and 1404. Each package of such insulating material shall be clearly labelled in accordance with CPSC 16-CFR, Parts 1209 and 1404. 4.3.21.4
Exposed attic insulation
All exposed insulation materials installed on attic floors shall have a critical radiant flux not less than 1200 watt/m2. 4.3.21.5
Testing
Tests for critical radiant flux shall be made in accordance with ASTM E 970.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.3.22 4.3.22.1
First edition Page 79/179
Dwelling unit separation Multi-family dwellings
--- Dwelling units in multi-family dwellings shall be separated from each other by wall and/or floor assemblies of not less than 1 hour fire-resistive rating when tested in accordance with ASTM E 119. --- Fire-resistive-rated floor-ceiling and wall assemblies shall extend to and be tight against the exterior wall, and wall assemblies shall extend to the underside of the roof sheathing. 4.3.22.1.1 Supporting construction
When floor assemblies are required to be fire-resistive, the supporting construction of such assemblies shall have an equal or greater fire-resistive rating. 4.3.22.2
Townhouses
--- Each townhouse shall be considered a separate building and separated by walls for exterior walls. --- A common 2-hour fire resistive wall is permitted for townhouses if such walls do not contain plumbing or mechanical equipment, ducts or vents in the cavity of the common wall. --- Electrical installations shall be installed in accordance with TTS 171 Electrical code. --- Penetrations of electrical outlet boxes shall be in accordance with this code. 4.3.22.2.1 Continuity
The common wall for townhouses shall be continuous from the foundation to the underside of the roof sheathing, deck or slab and shall extend the full length of the common wall. 4.3.22.2.2 Parapets
--- Where parapets are to be provided for townhouses as an extension of the common wall in accordance with the following: --- Where roof surfaces adjacent to the wall are at the same elevation, the parapet shall extend not less than 600mm above the roof surfaces. --- Where roof surfaces adjacent to the wall are at different elevations and the higher roof is not more than 800 mm above the lower roof, the parapet shall extend not less than 800mm above the lower roof surface. 4.3.22.2.3 Structural independence
Each individual townhouse shall be structurally independent. 4.3.22.3
Exceptions:
- Foundations supporting common walls. - Structural roof and wall covering sheathing from each unit may fasten to the common wall framing. - Non structural wall coverings. - Flashing at termination of roof covering over common wall. - Townhouses separated by a common two-hour fire-resistive wall.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.3.22.4
First edition Page 80/179
Sound transmission
Wall and floor-ceiling assemblies separating dwelling units shall provide airborne sound insulation for walls and both airborne and impact sound insulation for floor-ceiling assemblies. 4.3.22.4.1 Airborne sound
Airborne sound insulation for wall and floor-ceiling assemblies shall meet a Sound Transmission Class (STC) of 45 when tested in accordance with ASTM E 90. 4.3.22.4.2 Structural-borne sound
Floor/ceiling assemblies between dwelling units or between a dwelling unit and a public or service area within a structure shall have an impact insulation class ( IIC ) rating of not less than 45 when tested in accordance with ASTM E492. 4.3.22.5
Rated penetrations
Penetrations of wall or floor/ceiling assemblies are required to be fire resistant or should be protected in accordance with this section. 4.3.22.5.1 Through penetrations
--- Through penetrations of fire resistance rated wall or floor assemblies shall comply with this section. Exception - Where the penetrating items are steel, ferrous or copper pipes or steel conduits, the annular space shall be permitted to be protected as follows: 1. In concrete or masonry wall or floor assemblies where the penetrating items is a maximum of 150mm nominal diameter and the opening is a maximum of 90 000mm2, concrete, grout or mortar shall be permitted where installed in the full thickness of the wall or floor assemblies. 2. The material used to fill the annular space shall prevent the passage of flame and hot gases at the location of the penetration for the time period equivalent to the fire resistance rating of the construction. a)
Fire resistance rated assembly
Penetrations shall be installed as tested in the approved fire resistance rated assembly. b)
Penetration fire-stop system
Penetrations shall be protected by an approved penetration fire-stop system installed as tested in accordance with ASTM E814, with a minimum positive pressure differential of 0.25mm of water (3 Pa) and shall have an F rating of not less than the required fire resistance rating of the wall or floor /ceiling assembly penetrated. 4.3.22.5.2 Membrane penetrations
Where walls are required to have a minimum 1hour fire-resistance rating, recessed light fixtures shall be so installed such that the required fire resistance will not be reduced. 4.3.22.6 Non-rated penetrations
Penetrations of horizontal assemblies without a required fire resistance rating shall comply with this section. 4.3.22.6.1 Non combustible penetrating items
Non combustible penetrating items that connect not more than three stories are permitted provided that the annular space is filled with an approved non-combustible material or approved penetration fire-stop system. 4.3.22.6.2 Combustible penetrating items
Combustible penetrating items that connect not more than two stories are permitted provided that the annular space is filled with an approved material to resist the free passage of flame and the products of combustion.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.3.23
First edition Page 81/179
Moisture vapour barriers
4.3.23.1
Moisture control
In all framed walls, floors and roof/ceilings comprising elements of the building thermal envelope, an approved vapour barrier having a maximum rating of 1.0 perm, when tested in accordance with ASTM E96-92, (Standard Test Methods for Water Vapour Transmission of Materials), shall be installed on the warm side of the insulation.
4.3.24
Protection against decay
4.3.24.1
Location required
--- In areas subject to decay damage the following locations shall require the use of an approved species and grade of lumber, pressure preservatively treated, or decay-resistant. See Table 6 - Timber names for use in Trinidad & Tobago. --- Wood joists or the bottom of a wood structural floor when closer than 450mm or wood girders when closer than 300mm to exposed ground in crawl spaces or un-excavated area located within the periphery of the building foundation. --- All sills or plates, which rest on concrete or masonry exterior walls and are less than 200mm from exposed ground. --- Sills and sleepers on a concrete or masonry slab, which is in direct contact with the ground unless, separated from such slab by an impervious moisture barrier. --- The ends of wood girders entering exterior masonry or concrete walls having clearances of less than 15mm on tops, sides and ends. --- Wood siding, sheathing and wall framing on the exterior of a building have a clearance of less than 150mm from the ground. --- Wood structural members supporting moisture-permeable floors or roofs which are exposed to the weather, such as concrete or masonry slabs, unless separated from such floors or roofs by an impervious moisture barrier. --- Wood furring strips or other wood framing members attached directly to the interior of exterior masonry walls or concrete walls below grade except where an approved vapour barrier is applied between the wall and the furring strips or framing members.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
T n T local name
First edition Page 82/179
Normal Recommended use density External Internal Roofing Furniture Flooring Structure at 12% joinery joinery shingle
Resistant to Decay
Termites
Comments
Local woods Angelia
0.80
Balata
1.05
X X
X
X
beefwood
Bamboo
scaffolding
Bois gris
0.95
Boya mulatre or bois mulatre
0.80
Cajuca
0.48
Caribbean pine
0.80
Cedar
0.50
Crabwood or Crappo
0.70
Determa
0.62
Fiddlewood (black)
0.80
Fiddlewood (white)
0.72
Galba or Santa Maria
0.64
Gommier
0.56
Guatecare
1.04
X
X
resist to "Capricorn" fineleaf
X
X X -
X
X
X
X
X X
Laurier
Gumbo limbo Hog plum
see Gommier 0.48
Lay lay Mahoe
0.56
Mahoe or sterculia
0.60
X
X
X
X
X
X
X
X
maho cochon
Mahogany Mangrue (yellow) or Manni
0.70
Milkwood
0.56
X
X
Mora or Muru
0.96
X
Nargusta or white oliver
0.80
X
Olivier mangue or Poirier
0.80
Pink poui or apamate
0.56
Podocarp or W ild pine
0.56
Poui (black)
1.12
Purple heart
0.88
X
X
X
Redwood X
Resclu or W ater wood Saman
0.56
Sandbox
0.45
Sardine
0.80
Silk cotton tree
0.38
Simarouba
0.45
Snakewood or Galia
1.15
X
must be treated
packaging X
X
acajou blanc art craft
X
Tabebuia white or Calabash Tapana
0.80
Tapanare or Suradam
0.70
Teak
0.65
X
X
Tonka
1.08
X
X
X X
X
X
X X X
art craft
Table 6 - Timber names for use in Trinidad & Tobago (part 1)
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
T n T local name
First edition Page 83/179
Normal Recommended use density External Internal Roofing at 12% Furniture Flooring joinery joinery Structure shingle
Resistant to Decay
Comments
Termites
Imported woods
Tropical An gelique
0.80
Babeon
0.47
Bagasse
0.82
Cajuca
0.48
X
X
X
X
X
X
X
X
X
X
X
X
X
Eastern red cedar X
Gommier Green heart
1.04
Gronfoeloe
0.70
Kopie
0.82
Locust or Courbarli
0.85
Manbarklak
1.02
Pakuri
0.83
Wacapou
0.90
Wallaba
0.85
Wamara
basralocust
X
X
X
X X
X
X
X
x
X
X
X
bois caca
X
locust
X
X
X X
X
X
X
X
X
X X
X
1.20 X
0.58
X
X
0.85
X
Douglas fir
0.61
X
Pitchpine
0.52
iron wood
X
X
0.50
brown heart
X
bois lait or bois vache
X
Non tropical X X
X
X
from W Canada & USA
X
References TTS 16 40 000:1978
1978
USDA web site
2000
Magazine
2000
Les bois de Guyane
1990
Construire en bois de Guyane
1990
Prinicipaux bois indigènes et exotiques
1975
Table 6 - Timber names for use in Trinidad & Tobago (part 2)
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 84/179
4.3.24.1.1 Ground contact
All wood in contact with the ground and which supports permanent structures intended for human occupancy shall be approved pressure preservatively treated wood suitable for ground contact use. 4.3.24.1.2 Geographical areas
--- In geographical areas where experience has demonstrated a specific need, approved naturally durable or pressure preservatively treated wood shall be used for those portions of wood members which form the structural supports of buildings, balconies, porches, or similar permanent building appurtenances when such members are exposed to the weather without adequate protection from a roof, eaves, overhang or other covering which would prevent moisture or water accumulation on the surface or at joints between members. --- Such members may include: - Horizontal members such as girders, joists and decking. - Vertical members such as posts, poles and columns. - Both horizontal and vertical members. 4.3.24.1.3 Post, poles and columns
Posts, poles, and columns supporting permanent structures which are embedded in concrete in direct contact with the ground or embedded in concrete exposed to the weather shall be approved pressure preservatively treated wood suitable for ground contact use. 4.3.24.1.4 Wood columns
--- Wood columns shall be approved timber of natural decay resistance or approved pressure preservatively treated wood. --- Posts or columns must be supported by piers or metal pedestals projecting 50mm minimum above the floor or finish grade and are separated there from by an approved impervious moisture barrier. 4.3.24.2
Quality mark
Lumber and plywood required to be pressure preservatively treated shall bear the quality mark of an approved inspection agency which maintains continuing supervision, testing and inspection over the quality of the product. 4.3.24.2.1 Required information
The required quality mark on each piece of pressure preservatively treated lumber or plywood shall contain the following information: - Identification of the treating plant. - Type of preservative. - The minimum preservative retention. - End use for which product was treated. - Standard to which product was treated. - Identity of the approved inspection agency. - The designation “Dry,” if applicable. 4.3.24.3
Exception:
Quality marks on lumber less than 25 mm nominal thickness, or lumber less than nominal 25mm by 125mm or 50mm by 100mm or lumber 900mm or less in length shall be applied by stamping the faces of exterior pieces or by end labelling not less than 25 percent of the pieces of a bundled unit.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code 4.3.24.4
First edition Page 85/179
Fasteners
Fasteners for pressure preservative and fire-retardant-treated wood shall be of hot-dipped galvanised steel, stainless steel, silicon bronzes or copper.
4.3.25 4.3.25.1
Protection against termites Subterranean termite control
In areas susceptible to termite damage, methods of protection shall be by chemical soil treatment; pressure preservatively treated wood in accordance with the AWPA standards, naturally termite-resistant wood or physical barriers (such as metal or plastic termite shields), or any combination of these methods. 4.3.25.2
Chemical soil treatment
The concentration, rate of application and treatment method of the termiticide shall be consistent with and never less than the termiticide label. 4.3.25.3
Pressure preservatively treated and naturally resistant wood
See Table 6 -Timber names for use in Trinidad & Tobago for the list of naturally termite resistant wood. Pressure preservatively treated wood and naturally termite-resistant wood shall not be used as a physical barrier unless a barrier can be inspected for any termite shelter tubes around the inside and outside edges and joints of a barrier. 4.3.25.3.1 Field treatment
Field cut ends, notches and drilled holes of pressure preservatively treated wood shall be retreated in the field.
4.3.26 4.3.26.1
Flood resistant construction General
All buildings and structures erected in areas prone to flooding and classified as either flood hazard areas or coastal high hazard areas shall be constructed and elevated as required by the provisions contained in this section. 4.3.26.1.1 Structural systems
All structural systems of all buildings and structures shall be designed, connected and anchored to resist flotation, collapse or permanent lateral movement due to structural loads and stresses from flooding equal to the design flood elevation. 4.3.26.1.2 Flood resistant construction
All buildings and structures erected in flood hazard zones shall be constructed by methods and practices that minimise flood damage. 4.3.26.1.3 Establishing the design flood elevation
The design flood elevation shall be used to define areas prone to flooding, and shall describe, at a minimum, the base flood elevation at the depth or peak elevation of flooding (including wave height) which has a 1-percent (100year flood) or greater chance of being equated or exceeded in any given year. This level should be determined by the physical planning standards 4.3.26.1.4 Lowest floor
The lowest floor shall be the floor of the lowest enclosed area, including basement, but excluding any unfurnished flood-resistant enclosure that is useable solely for vehicle parking, building access, or limited storage provided that such enclosure is not built so as to render the building or structure in violation of this Section.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 86/179
4.3.26.1.5 Protection of mechanical and electrical systems
--- New and replacement electrical equipment, ventilating, air conditioning plumbing connections, and other service equipment shall be located at or above the design flood elevation. --- Electrical wiring and outlets, switches, junction boxes and panels shall be elevated to or above the design flood elevation for location of such items in wet locations. --- Ducts and duct installation shall not be installed below the design flood elevation. 4.3.26.1.6 Protection of water supply and sanitary sewage systems
--- New and replacement water supply systems shall be designed to minimise infiltration of flood waters into the systems in accordance with the plumbing provisions of this code. --- New and replacement sanitary sewage systems shall be designed to minimise infiltration of floodwaters into systems and discharges from systems into floodwaters. 4.3.26.1.7 Flood resistant materials
--- Building materials used below the design flood elevation shall comply with the following: - all wood, including floor sheathing shall be pressure preservatively treated, or decay-resistant. --- For the list of foreign and local woods see Table 6 - Timber names for use in Trinidad & Tobago 4.3.26.1.8 As-built elevation certifications
A licensed land surveyor or registered design professional shall certify that the building or structure is in compliance with the elevation required. 4.3.26.2
Flood hazard areas
All areas, which have been determined to be prone to flooding but not subject to high velocity wave action shall be designated as flood hazard areas. 4.3.26.2.1 Elevation requirements
--- Buildings and structures shall have lowest floors elevated to or above the design flood elevation. --- In areas of shallow flooding, buildings and structures shall have the lowest floor (including basement) elevated at least as high above the highs natural adjacent grade as the depth number specified in metre, or at least 600mm if a depth number is not specified; --- Basement floors that are below grade on all sides shall be elevated to or above the design flood elevation. 4.3.26.2.2 Enclosed area below design flood elevation
Enclosed areas, including crawl spaces, that are below the design flood elevation shall: a) Be used solely for parking of vehicles, building access, or storage, and b) Be provided with flood openings, which shall meet the following criteria: - There shall be a minimum of two openings on different sides of each enclosed area; if a building has more than one enclosed area below the design flood elevation, each area shall have openings on exterior walls. - The total net area of all openings shall be at least 1/150 of enclosed area. - The bottom of each opening shall be 300mm or less above the adjacent ground level. - Openings shall be at least 75mm in diameter. - Any louvers, screens or other opening covers shall allow the automatic flow of floodwaters into and out of the enclosed area. - Openings installed in doors and windows, which meet requirement (a) through (e), are acceptable; however, doors and windows without installed openings do not meet the requirement of this section.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code 4.3.27
First edition Page 87/179
Coastal high hazard areas
--- Areas, which have been determined to be subject to wave heights in excess of 900mm or subject to high velocity wave action or wave induced erosion, shall be designated as coastal high hazard areas. --- All buildings and structures erected in coastal high hazard areas shall be designated and constructed in accordance with this Sections. 4.3.27.1
Elevation requirements
1. All buildings and structures erected within coastal high hazard areas shall be elevated so that the lowest portion of all structural members supporting the lowest floor, with the exception of mat or raft foundations, piling, pile caps, columns, grade beams and bracing, is located at or above the design flood elevation. 2. Basement floors that are below grade on all sides are prohibited. 3. The use of fill for structural support is prohibited. 4. The placement of fill beneath buildings and structures is prohibited. 4.3.27.2
Foundations
--- All buildings and structures erected in coastal high hazard areas shall be supported on pilings or columns and shall be adequately anchored to such pilings or columns. Piling shall have adequate soil penetrations to resist the combined wave and wind loads (lateral and uplift). Water loading values used shall be those associated with the design flood. Wind loading values shall be those required by this code. Pile embedment shall include consideration of decreased resistance capacity caused by scour of soil strata surrounding the piling. --- Mat, raft, or other foundations, which support columns, shall not be permitted where soil investigations that indicate that soil material under the mat, raft, or other foundation is subject to scour or erosion from wave-velocity flow conditions. 4.3.27.3
Walls below design flood elevation
Walls and partitions are permitted below the elevated floor, provided that such walls and partitions are not part of the structural support of the building or structure and: a)
Are constructed with insect screening or open lattice, or
b) Designed to break away or collapse without causing collapse, displacement or other structural damage to the elevated portion of the building or supporting foundation system. c) Such walls, framing, and connections shall have a design safe loading resistance of not less than 0.50 kN/m2 and no more than 1.00 kN/m2; or d) Where wind loading values of this code exceed 1.00 kN/m2, a registered design professional shall certify the following: i. Collapse of walls and partitions below the design flood elevation shall result from a water load less than that which would occur during the design flood, and ii. The elevated portion of the building and supporting foundation system shall not be subject to collapse, displacement, or other structural damage due to the effects of wind and flood loads acting simultaneously on all building components (structural and non-structural). Water loading values used shall be those associated with the design flood. Wind loading values used shall be those required by this code. 4.3.27.4
Enclosed areas below design flood elevation
Enclosed areas below the design flood elevation shall be used solely for parking of vehicles, building access, or Storage.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.4
First edition Page 88/179
Basic materials
4.4.1 4.4.1.1
Reinforced Concrete Materials
Concrete shall be manufactured from ordinary Portland or approved cement, sand, gravel and water. 4.4.1.1.1 The cement shall be fresh and contained in unopened bags, which have been well protected from moisture and stored above the ground. 4.4.1.1.2 The sand shall be clean (i.e. free of clayey lumps, organic materials and broken shells), natural sharp sand, preferably taken from an inland source. Beach sand shall not be used. 4.4.1.1.3 The coarse aggregate shall be of crushed stone or gravel with a size between 10 and 25mm. The aggregate shall be free of dust coating. In areas where only broken stone is available, care shall be taken to use stone as near to 20 mm as practicable. 4.4.1.1.4
4.4.1.2
Only clean fresh water of a potable standard shall be used for the mixing of concrete.
Mixing
4.4.1.2.1 A concrete mix producing concrete with minimum compressive cube strength of 21 N/mm2 at 28 days or 16.8 N/mm2 at 7 days shall be used. The approximate proportions normally required to produce such a mix are 42 kg (1 bag) of cement, 0.056 m3 (1 wheelbarrow) of sand, and 0.084 m3 (1½ wheelbarrow) of aggregates and approximately 18 l of water.
Note: any moisture affects the maximum amount of water required, which may be present in the aggregate. The quality is therefore reduced when the aggregate is wet. 4.4.1.2.2 The cement shall be added by the bag. The fine and coarse aggregates shall be measured in cubic metre (m3) and the water shall be measured in litre (l). 4.4.1.2.3 For coastal environment conditions the mix shall be upgraded to 42 kg (1 bag) of cement, 0.056 m3 (1 wheelbarrow) of sand, 0.056 m3 (1 wheelbarrow) of aggregate and approximately 15 l of water. 4.4.1.2.4 The concrete shall be mixed by hand or preferably by machine until there are no visible areas of unmixed materials and a uniform colour is obtained.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 89/179
Trinidad and Tobago
Metric system Compression at 28 days
Cement
Sand
Gravel
Number of wheelbarrow of
Number of wheelbarrow of
Cement
Sand
Gravel
Number of bag of
Proportion for one cubic metre (1m3) Type of concrete
kN/m2
Concrete utilization
kg
42 kg bag
litre
litre
controlled concrete
concrete without any control
Grade "E"
150
4
335
665
nscr
nscr
1-3-6
1
1.5
3
Back filling concrete
Grade "D"
250
6
400
600
nscr
nscr
1-2-4
1
1
2
Foundation
Grade "C"
300
7
335
665
23,000
15,000
1-2-3
1
1
1.5
Grade "B"
350
8
335
665
27,000
18,000
1-2-2
1
1
1
Beam and column
Grade "A"
400
10
335
665
30,000
20,000
2-3-4
2
1.5
2
Exposed concrete Coastal exposition
Note : Volume of wheelbarrow
57
equivalent
2
litres
Slab and protected concrete
in the type of concrete
Table 7 - Concrete composition
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.4.1.3
First edition Page 90/179
Form work
4.4.1.3.1 The form work into which the concrete is to be placed shall be strongly constructed of straight timber or any adequate materials so braced that no movement or deformation is caused by the wet concrete under normal construction loads 4.4.1.3.2 leakage.
4.4.1.4
The form work shall have close fitting joints so that no fine aggregate, cement or water is lost through
Reinforcement
4.4.1.4.1 The minimum requirement for reinforcement steel shall be bars of grade 250 i.e. plain mild steel bars of 250 N/mm2 (minimum yield) stress. This section is based on grade 250 bars; however, higher grades of plain or deformed bars may be used. 4.4.1.4.2
Bar bending
The minimum pin diameter size for steel bar bending in accordance with TTS 583:2000 must be as shown in Table 8. Table 8 - Recommended minimum size bending
Steel grade
Bar size " d " In mm
4.4.1.4.3
250
420
6 to 16mm
2.5d (15 to 40mm)
4d (20 to 64mm)
20 & 25mm
Not applicable
5d (100 or 125mm)
32 & 40mm
Not applicable
7d (225 or 300mm)
Bar welding
Welding is not allowed. 4.4.1.4.4 Reinforcement steel, which shall be free of loose mill scale (rust), shall be properly tied together by mild steel tying wire. The whole assembly shall be positioned within the form work with appropriately sized concrete spacers so that the correct concrete cover to the steel is maintained. 4.4.1.4.5 Concrete shall not be vibrated by direct contact between the vibrating instrument and reinforcing bar. The practice of vibrating the form work shall also not be permitted as this may displace the steel fixings. The practice of vibrating the concrete shall therefore be used with caution. 4.4.1.4.6 The recommended concrete covers for normal conditions and coastal environmental conditions are given in Table 9.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 91/179
Table 9 — Recommended concrete cover
Type
Concrete cover in mm Normal conditions
Coastal environmental conditions
Slabs
25
35
Beams
30
40
Columns
30
40
Surfaces In contact with earth
75
95
Note: The recommended concrete cover for coastal environmental conditions is based on an increase of 25 % for normal conditions.
4.4.1.5
Placing Concrete
4.4.1.5.1 Form work shall be thoroughly cleaned to remove sawdust, bits of wood, wire and other debris before placing concrete in it. 4.4.1.5.2 Transporting the concrete over long distances (unless special equipment is used) shall be avoided to prevent segregation of its components. 4.4.1.5.3 All runways and routes between the mixer and the area where the concrete is to be used should be set up beforehand and kept clear, so that the placing of concrete can proceed smoothly without interruptions. 4.4.1.5.4 The poured concrete shall be compacted in the form work by vibration or rodding, so that dense concrete is obtained. Where necessary, chutes shall be used to place concrete in tight areas such as column forms. 4.4.1.5.5 Where floor slabs or roof slabs cannot be poured in one operation, construction joints shall be used. Professional assistance shall be sought on the proper placing of the construction joints in suspended slabs.
4.4.1.6
Curing
4.4.1.6.1 The optimum concrete strength shall be obtained by proper curing. To achieve this, the curing concrete shall be kept moist by wetting with water for four (4) days after it is poured. 4.4.1.6.2 Proprietary curing compounds may be used in accordance with the manufacturer’s instructions.
4.4.1.7
Stripping of form work
The side form work of beams and columns may be removed from the fresh concrete after 24 hours. The bottom form work and props for suspended beams and slabs shall remain in place for not less than 10 days.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.4.2
4.4.2.1
First edition Page 92/179
Timber
Type of wood
Walls, floors and roofs can be constructed of approved structural timber. See Table 6. 4.4.2.2
Preservatively treated lumber
Only treated timber should be used and shall also be identified. 4.4.2.3
Moisture
The timber should be sound, straight and well seasoned timber with moisture content between 15% and 20%.
4.4.3
4.4.3.1
Metal
Structural steel
Material conforming to one following standard specifications (latest date of issue) is approved for use under this code: - Structural steel, ASTM A36 is the all purpose carbon steel used in building construction. - Welded and seamless steel pipe, ASTM A53, grade B. 4.4.3.2
Structural shapes
All shapes are published in the ASTM A6 and the principals used are: - W shapes have essentially parallel flange surfaces. The profile of a W shape of a given nominal depth and weight. - HP bearing pile shapes have essentially parallel flange surfaces and equal web and flange thickness. - S beam and C channel have a slope on their flange surfaces. - L angles shape with equal and unequal leg. - Pipe and structural tubing. 4.4.3.3
Bolts
Steel bolts shall conform to one of the following standard specification: - Low carbon steel externally and internally threaded standard fasteners, ASTM A307. - High strength bolts for structural steel joints, ASTM A325. - Quenched and tempered steel bolts and nuts, ASTM A449.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
4.5
First edition Page 93/179
Alternate materials and types of construction
4.5.1
General
The provisions of this Code are not intended to prevent the use of types of construction or materials or methods of designs as alternates to the standards herein set forth. Such alternates shall be offered for approval and their consideration shall be as specified in Annex A – Administration and Enforcement.
4.5.2
Standards
The types of Construction or materials or methods of design referred to in this Code shall be considered as standards of quality and strength. New types of construction or materials or methods of design shall be at least equal to these standards for the corresponding use intended.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 94/179
Strip footing Slab on grade
Slab on grade 100mm min
Pad footing 300mm min 600mm 1000mm min
Suspended slab Suspended slab
125mm min 300mm min
125mm min
600mm
300mm min
Crawl space 300mm min
450 Crawl space 300mm min
300mm min
On pile
Raft Slab on grade 100mm min.
300 450
Fig 34 - Foundation-types
150mm blockwork
r.c. tie beam
0.15mm polythene damp proof course
100mm slab minimum 50mm sand blinding
300mm minimum grade
well compacted gravel or marl in 100mm layers 150mm blockwork minimum
600mm min Local thickening 100 x 100mm min
450
Fig 35 - Details of ground floor slab on grade
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
5
First edition Page 95/179
Foundations
5.1
General
5.1.1
Load bearing walls and columns
5.1.1.1
--- All loads bearing walls and columns shall be supported on any of the following reinforced concrete footings: a) Pad footing b) Strip footing c) On pile d) Raft --- The above reinforced concrete footings are shown in Figure 34 - Foundations types. --- The two last solutions shall be engineered design. 5.1.1.2 Interior walls shall be supported by thickening the slab under the wall and suitably reinforcing it. The foundation should be located on a layer of soil or rock with good bearing characteristics. Such soils include dense sands, marl, other granular materials and stiff clays. 5.1.1.3 The foundation shall be cast not less than 600 mm below ground, its thickness not less than 225 mm and its width not less than 450 mm or a minimum of three times the width of the wall immediately supported by it (see Figures 36 - Arrangement of strip footing). 5.1.1.4 When separate reinforced concrete columns or concrete block columns are used they shall be supported preferably by square footings not less than 600 mm per side, 225 mm thick and 1000mm depth (see Figure 37 Typical spread footing detail). 5.1.1.5 When the ground is subject to drying (cracks or fissures) the minimum depth above should be increased under the advice of a professional engineer.
--- To avoid this increase in depth, the foundation should be protected by surface paving.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
5.1.2
First edition Page 96/179
Reinforcement
5.1.2.1 For strip footings, the minimum reinforcement shall consist of a minimum of three 10 mm diameter bars placed longitudinally and 10 mm diameter bars placed transversely no more than 600 mm between their centres (see Figure 36). 5.1.2.2 For column footings, the minimum reinforcement shall be 12 mm diameter bars at 150 mm between centres in both directions forming a mesh (see Figure 37).
Bars may be suitably cranked bent or lapped at the ends. Lapped or cranked lengths shall be a minimum 5.1.2.3 of 40 times the diameter of the bars being joined. Table 10 gives the minimum lap lengths for steel reinforcement.
Table 10 — Minimum lap lengths for steel reinforcement
Bar diameter
Minimum lap length
mm
mm
6
300
8
350
10
400
12
600
16
750
Mesh
150 or one square, whichever is greater
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 97/179
1000
150mm blockwork
150mm blockwork
125mm slab minimum
r.c. tie beam
125mm slab minimum
grade
grade
300 mm min crawl space
Crawl space
75
75
150mm blockwork minimum
600mm mini
225
if 200mm blockwork
225 75
75
450mm minimum
600mm min 3 times 200mm
Fig 36 - Arrangement for strip footing 150mm and 200mm vertical core blocks
30
75 300 mm
r.c. column
75
75mm minimum
1000 min 600mm minimum 225 75 600mm minimum
12mm rods 150mm crs.
Fig 37 - Typical pad footing details
File # Small building code 2004_draft
Date 1 July, 2004
File # Small building code 2004_draft Masonry Suspended ground floor slab with crawl space
R.C./ Masonry Suspended ground floor slab with crawl space
Sloping site
Masonry Suspended first floor slab Ground floor slab suspended or on grade
R.C./ Masonry Suspended first floor slab
no
ta
c
Shear panel
ble
Masonry Ground floor slab suspended or on grade
p ta ce
Flat site
Trinidad & Tobago Small Building Code First edition Page 98/179
Fig 38 - 1 and 2 level house type
Date 1 July, 2004
First edition Page 99/179
102
152
102 190
190
Concrete blocks
390
Clay blocks
290
152
152
152
203
390
Clay blocks
390
190
Concrete blocks
152 190
or
190
390
Load bearing blocks
390
Filled with concrete
or
190
102
190
390
Non load bearing blocks
190
Trinidad & Tobago Small Building Code
Fig 39 - Load & non load bearing clay or concrete blocks
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 100/179
Ring beam 200mm minimum
First floor
Minimum slab thickness see table B4 Ring beam 200mm minimum Maximum span see table B4
Ground level
150mm blockwork
150mm blockwork
Crawl space 300 mm minimum
See details figures B14 and/or B 15-1
Fig 40 - 2 level house - Typical cross section masonry blocks
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
6
First edition Page 101/179
Vertical structures
6.1
Concrete and masonry
6.1.1
Masonry block walls
6.1.1.1
General
This section outlines the requirements for structural masonry construction using shear panels for single and two storey structures as configured in Figure 38 - 1or 2 level house type.
6.1.1.2
Workmanship
Cavities shall be clean and substantially free from mortar droppings. Reinforcement shall be placed centrally and/or properly spaced from the masonry. Reinforcement shall be adequately lapped and secured. The procedure for applying concrete as outlined in Clause 4.4.1.5 shall be adhered to.
6.1.1.3
Hollow masonry blocks
Hollow clay block units shall conform to the latest edition of the ASTM C652-95a Hollow Brick 6.1.1.3.1 (Hollow Masonry Units Made from Clay or Shale) and/or ASTM C34-96 Structural Clay Load-Bearing Wall Tile. See TTS 587:2003 and TTS 588:2003. --- Grade 3 clay blocks cannot be considered as structural. 6.1.1.3.2 Load bearing concrete masonry block units shall conform to the latest edition of TTS 16 35 508 Specification for Load Bearing Concrete Blocks. 6.1.1.3.3 Non-load bearing interior walls or partitions may be constructed using blocks with a thickness of 100 mm or less. Concrete masonry block units for such application shall conform to the latest edition of TTS 16 35 509 Specification for Non-load Bearing Concrete Blocks. 6.1.1.3.4
6.1.1.4
Figure 39 shows the various types of load bearing and non-load bearing masonry blocks.
Shear panels
6.1.1.4.1 A shear panel (see Figures 17 and 18 - Shear panel) is a portion or section of a 150mm exterior wall that performs the function of resisting lateral earthquake or wind forces. 6.1.1.4.2
Where masonry is used there shall be a shear wall on each exterior wall of every house.
6.1.1.4.3 A shear panel should be 1.8 m in horizontal dimension along the face of the wall and a minimum of 150 mm in block and wall thickness extending from floor to ring beam, with no openings or penetrations. If the shear panel must be divided in two part the total of horizontal dimension increase to 2.4m with a minimum of 1000mm for the smallest part. (See Figures 17 & 18).
--- Figures 41 & 42 shows the various configurations and applications of a shear panel, vertical stiffeners and openings:
File # Small building code 2004_draft
Date 1 July, 2004
Max 1800mm Max 1800mm
For ventilation blocks Shear panel
Alternative for ventilation integrated to the opening
Min 400mm
First edition Page 102/179
horizontal reinforcement every three rows
Trinidad & Tobago Small Building Code
Fig 41 - Typical external wall arrangement - vertical core blocks
File # Small building code 2004_draft
Date 1 July, 2004
File # Small building code 2004_draft Max 1800mm
Shear panel Shear panel of 1800 mm
Shear panel of 1800 mm
For ventilation blocks
Max 1800mm
Stiffener every 1800 mm
Alternative for ventilation integrated to the opening
Min 400mm
horizontal reinforcement every three rows
Trinidad & Tobago Small Building Code First edition Page 103/179
Fig 42 - Typical external wall arrangement - horizontal core blocks
Date 1 July, 2004
Trinidad & Tobago Small Building Code
6.1.1.5
First edition Page 104/179
Block laying
6.1.1.5.1 41 & 42).
Blocks shall be laid in half bond courses which have been aligned using lines and levels (see Figures
6.1.1.5.2 Walls at junctions and corners shall be bonded to each other by reinforcement and also interlocked in half bond. All walls shall be tied to columns or to reinforced corners at every second course. 6.1.1.5.3 Horizontal and vertical mortar joints shall be a minimum thickness of 12 mm and shall be properly filled with mortar.
6.1.1.6
Mortar
6.1.1.6.1 Mortar shall be made using, by volume, 1 part of ordinary Portland cement and a maximum of 4 parts of clean sifted plastering sand. 6.1.1.6.2 Mortar shall be mixed by hand or preferably by a machine until the ingredients are thoroughly mixed (not less than 3 minutes by machine). A minimum amount of water shall be added to the dry mixture to allow for workability. There shall be no re-mixing of mortar. 6.1.1.6.3
6.1.1.7
Mortar shall be mixed in appropriate amounts so it is completely used within 2 hours.
Reinforcement
6.1.1.7.1
Shear panel
See Figures 17 and 18 with vertical and horizontal core blocks. a)
Vertical reinforcement
i.
With vertical core blocks
Shear panels shall be vertically reinforced using 12 mm diameter bars placed a distance of 400 mm between centres in solid grouted cells. A 1.8 m shear panel would then have five 12 mm diameter bars vertically placed. See Figure 17. ii.
With horizontal core blocks
Shear panels shall be vertically reinforced using a frame of 2 vertical columns 250mm x 150 mm minimum with 4 x 12 mm diameter bars placed vertically and 6mm diameter bar stirrup each 150 mm in solid concrete. See Figure 18. b) Vertical reinforcement bars shall be adequately lapped and secured to hook dowels anchored both in the foundation and the ring beam. c) Horizontal reinforcement shall be provided using masonry mesh 50 mm × 50 mm × 3 mm (2 in × 2 in × 10 G) or an equivalent every two rows. (See Figures 46 & 47).
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 105/179
2 dia. 12mm bar 2 dia. 12mm bar
2 dia. 12mm bar
Max 1800mm 2 dia. 12mm bar
2 dia. 12mm bar 2 dia. 10mm bar Ground level
Window
Door
Fig 43 - Openings and lintels
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 106/179
Part elevation Vertical reinforcement
In situ concrete
Part plan
Part elevation Vertical reinforcement
In situ concrete
Part plan
Fig 44 - Typical wall corner & intersection - vertical core blocks
File # Small building code 2004_draft
Date 1 July, 2004
First edition Page 107/179
200 mm min
Trinidad & Tobago Small Building Code
Part elevation Vertical reinforcement 200 mm min
In situ concrete
Part elevation 250 mm min
200 mm min
Part plan
Vertical reinforcement
In situ concrete
Part plan
Fig 45 - Typical wall corner & intersection - horizontal core blocks
File # Small building code 2004_draft
Date 1 July, 2004
File # Small building code 2004_draft Phase 0
dia 12mm
zontal reinforcement ry three rows
Horizontal reinforcement every three rows
Form work
2 1
3
Foundation
Vertical stiffener locations
Phase 1 Block laying and horizontal reinforcement
Phase 2 Vertical reinforcement and formwork
Phase 3 Concreting
1 dia.12mm vertical
1 dia.10mm horizontal
Acceptable horizontal reinforcement
Trinidad & Tobago Small Building Code First edition Page 108/179
1800
1800
Fig 46 - Typical wall reinforcement and phasing construction
Horizontal core blocks
Date 1 July, 2004
File # Small building code 2004_draft dia 12mm
Phase 0
Horizontal reinforcement every two course
2
Concrete
13
1
dia 12mm x 1 000mm
Phase 1
12
14
Last Phase
40mm Foundation
2
4
Concrete
1
3
Phase 2
2
4
6
8
1
3
5
7
Phase "n"
2
4
6
Concrete
1
3
5
Phase 3
Acceptable horizontal reinforcement
Trinidad & Tobago Small Building Code First edition Page 109/179
Fig 47 - Typical wall reinforcement and phasing construction
Vertical core blocks
Date 1 July, 2004
Trinidad & Tobago Small Building Code
6.1.1.8
First edition Page 110/179
Openings
6.1.1.8.1 All openings of 600 mm or greater in any direction shall be reinforced both horizontally and vertically with a minimum of two 10 mm diameter bars. All bars shall extend a distance not less than 600 mm beyond each corner of the opening or otherwise anchored by a 300 mm bend inside the concrete frame (see Figure 43 Openings and lintels). 6.1.1.8.2
Lintels with a span of 600 mm or less shall be horizontally reinforced with two 10 mm diameter bars.
6.1.1.8.3 Lintels with a span ranging from 1.2 m to 1.8 m shall be horizontally and vertically reinforced with two 12 mm bars. 6.1.1.8.4
6.1.1.9
For large openings refer to Clause - Lintels.
Load bearing walls (external and internal)
6.1.1.9.1 Masonry walls other than those described above shall be reinforced as follows:
a) Three 10 mm diameter bars placed vertically at corners (see Figures 44 & 45). b) Four 10 mm diameter bars placed vertically at intersections (see Figures 44 & 45). c) Two 10 mm diameter bars placed vertically at jambs of doors and windows (see Figure 43). d) For vertical wall reinforcement (stiffener) 12 mm diameter bars shall be used spaced 1.8m apart (see Figures 46 & 47). e) Horizontal reinforcement every three rows (see Figures 46 & 47).
6.1.1.10
Non-load bearing walls (internal walls)
The recommended minimum reinforcement for non load bearing walls with concrete block construction (refer to Figures 48 & 49) shall be as follows: a) One 10 mm diameter bar shall be placed vertically at corners. b) One 10 mm diameter bar shall be placed vertically at junctions. c) For vertical wall reinforcement 10 mm bars shall be spaced at a maximum of 2.5 m apart.
6.1.1.11
Concrete in fill
6.1.1.11.1 Vertical core blocks a) Load bearing walls shall be filled with 1:2:4 nominal mix (refer to Table 7) into the block cores. The concrete shall be properly compacted, with concrete being added after every two courses of block erection (see Figure 47). b) Non-load bearing walls shall be filled with grout or fine aggregate concrete as the work proceeds (see Figure 47).
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 111/179
c) Pouring of concrete into vertical block cores shall be stopped 40 mm below the top of the block in order to form a key at joints (see Figure 47). d) The wall reinforcement shall be securely anchored in the wall footing and the ring beam. Horizontal reinforcement shall be embedded in mortar and shall be continuous through intersections and corners (see Figure 47).
Ring beam
2.50m maximum
Frame
2.50m maximum
Frame
External wall 150mm minimum
Stifener each 2.50m maximum
Fig 48 - Internal wall arrangement and reinforcement - Vertical core
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 112/179
Ring beam
2.50m maximum
2.50m maximum
Frame
External wall 150mm minimum
Frame
Stifener each 2.50m maximum
Fig 49 - Internal wall arrangement and reinforcement - Horizontal core
Ring beam - junction reinforcement Concrete beam 150mm min x 200mm min Concrete grade "B" or "C" min
2 x 2 dia 12mm/1m angles
Dia 6mm stirrup details 100mm
150mm
200mm min
100mm
Ring beam - corner reinforcement
4 dia. 12mm bars
2 x 3 dia 12mm/1m angles
150mm min 100mm 300mm
Fig 50 - Ring beam reinforcement
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 113/179
6.1.1.11.2 Horizontal core blocks
a) Vertical stiffeners and columns integrated in the wall shall be filled with 1:2:4 nominal mix (refer to table B 1) into the form work. The concrete shall be properly poured and compacted after total block erection in order to insure a good wall interlocking (see Figure 46). b) The wall reinforcement shall be securely anchored in the wall footing and the ring beam. Horizontal reinforcement shall be embedded in mortar and shall be continuous through intersections and corners (see Figure 46).
6.1.1.12
Ring beams
6.1.1.12.1 All walls shall be finished at the top by a reinforced concrete ring beam not less than 200 mm in depth. 6.1.1.12.2 The minimum ring beam reinforcement shall be four 12 mm diameter bars with 6 mm diameter stirrups placed 300 mm between centres. The beam width shall be a minimum of 150 mm without plaster (see Figure 50). 6.1.1.12.3 The corners of ring beams shall be reinforced as shown in Figure 50.
6.1.1.13
Isolated columns
Where columns are required for porches, carports etc., construction shall be as follows: a) b) two. c)
Minimum dimensions shall be 200 mm × 200 mm. Columns shall be formed by form work on four sides or form work on two sides with block work on the other Square columns:
i. The minimum column reinforcement shall be four 12 mm diameter bars with 6 mm diameter stirrups placed 150 mm between centres. ii. Isolated columns may be formed by 200 x 200 x 200mm concrete blocks filled and reinforced as required above. d)
Round columns:
i. Round columns with varying cross-section (fancy columns) shall have a minimum section of 200mm diameter and shall be reinforced with six (6) 12mm diameter bars with 6mm diameter round stirrups placed 150mm between centres.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
6.1.1.14
First edition Page 114/179
Lintels
6.1.1.14.1 Reinforced concrete lintels shall span all door and window openings and shall extend beyond the jambs by not less than 150 mm. 6.1.1.14.2 The lintel shall be 200 mm deep for openings not greater than 2.5 m in width and 300mm deep for greater span between 2.5m and 4m. 6.1.1.14.3 The reinforcement of the lintel shall be four 12 mm diameter bars and 6 mm diameter stirrups placed 200 mm between centres. Reinforcement bars shall be placed in lintels ditto as shown in Figure 50 for ring beam.
6.1.1.15
Chasing
The chasing of walls for the installation of services shall be carefully controlled. Horizontal chases at any one level shall be restricted to 0.7 m in length and only one side of the wall shall be chased. Chasing shall be done before the walls are plastered and then filled with concrete. No chasing of structural members shall be permitted.
6.1.1.16
Services
6.1.1.16.1 Services shall not be carried through shear panels. 6.1.1.16.2 Where services through a structural member other than a shear panel are unavoidable, a sleeve, preferably metallic, shall be provided during the casting operation. The maximum external diameter of the sleeve shall be 25 mm. The minimum spacing between sleeves shall be 150 mm.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 115/179
Section on shear panel
First floor
Section on beam only Beam see table B7
Minimum slab thickness see table B4
Ground level
150mm blockwork see shear panel
Crawl space 300 mm minimum
See details figures B14 and/or B 15-1
Fig 51 - 2 level house Typical cross section columns, beams and shear panel
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
6.1.2
6.1.2.1
First edition Page 116/179
Columns, beams and shear panel structure
General
This section outlines the requirements for structural columns and beams construction using shear panels for single and two storey structures as configured in Figures 12 and 13 for 1or 2 level house type.
6.1.2.2
Shear panels
Ditto "Shear panels" in previous paragraph "Masonry block walls" and "Reinforcement".
6.1.2.3
Columns
Columns construction shall be as follows: 6.1.2.3.1
Sizes
Minimum dimensions shall be 250 mm × 250 mm. 6.1.2.3.2
Form work
Columns shall be formed by form-work on four sides or form-work on two sides with block work on the other two. 6.1.2.3.3
a)
Reinforcement
Square columns
The minimum column reinforcement shall be four 12mm diameter bars with 6mm diameter stirrups placed 150 mm between centres. b)
Round columns
Where round columns are used, or round columns with varying cross-section (fancy columns) shall have a minimum section of 250mm diameter and shall be reinforced with six (6) 12mm diameter bars with 6mm diameter round stirrups placed 100mm between centres. 6.1.2.3.4
Concrete
--- Columns shall be filled with 1:1:1 nominal mix (refer to Table 7). --- The concrete shall be properly compacted and poured at one time with no joints present for any height of column.
6.1.2.4
Beams
Where beams are used, construction shall be as follows: 6.1.2.4.1
Dimensions
- Maximum span 5000mm - Minimum section - See Tables 11, 12, 13, 14 - Total height not less than 1/12 span with 300mm minimum. (see Tables 11, 12, 13, 14)
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 117/179 Beam # 1 Beam section
Live Load Beam maximum span (metres) 3.00 4.00 5.00 3.00 Office floor 2.50 kN/m2 4.00 5.00 Small industrial floor and storage 5 kN/m2 2.50 3.50 4.50 Horizontal span 3.00 Roof 1kN/m2 4.00 5.00 Domestic floor 2.00 kN/m2
Width
Slab Total height thick.
Main reinforcement
Vert. stirrups
Top steel on bearing
Dia. 1 Number
Dia. 2 Number Total
Dia. 1 Number
Dia. 2
Number
Total
Dia.
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm) 16 16 16 16 16 16
min. 2 4 7 2 4 7
mm2 594 944 1,608 518 1,016 1,540
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm) 12 16 16 12 16 16
min. 1 2 4 1 2 4
mm2 330 524 894 288 565 856
(mm) 5 5 5 5 5 5
(mm) 250 250 350 200 350 400
(mm) 300 400 450 350 400 500
(mm) 100 125 150 100 125 150
250 300 400
300 400 500
100 125 150
12 12 12
2 2 2
12 16 16
2 3 6
465 856 1,410
12 12 12
2 2 2
10 12 16
1 3 3
258 476 783
250 300 350
300 400 500
100 125 150
12 12 12
2 2 2
12 16 16
3 3 6
542 876 1,326
12 12 12
2 2 2
10 12 16
1 3 3
Nb vert. Bar/stir.
Space (mn)
Total stirrup
2 4 4 2 4 4
mini 50 50 50 50 50 50
maxi 210 250 250 250 250 250
5 5 5
2 4 4
50 50 50
220 250 250
19 23 30
301 264 736
5 5 5
2 4 4
50 50 50
220 250 250
22 27 33
Nb vert. Bar/stir.
23 27 33 20 27 33
Beam # 2 Beam section
Live Load Beam maximum span (metres) 3.00 4.00 5.00 3.00 Office floor 2.50 kN/m2 4.00 5.00 Small industrial floor and storage 5 kN/m2 2.50 3.50 4.50 Horizontal span 3.00 Roof 1kN/m2 4.00 5.00 Domestic floor 2.00 kN/m2
Width
Slab Total height thick.
Main reinforcement
Vert. stirrups
Top steel on bearing
Dia. 1 Number
Dia.
Number Total
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm) 10 12 16 10 12 16
min. 2 4 4 2 5 4
mm2 384 691 1,008 394 712 1,039
Dia. 1 Number
Dia. 2
Number
Total
Dia.
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm)
min.
12 16
2 2
12 16
2 2
mm2 214 384 560 219 395 577
(mm) 5 5 5 5 5 5
(mm) 150 200 250 150 200 250
(mm) 350 400 500 350 400 500
(mm) 100 125 150 100 125 150
150 200 250
300 400 500
100 125 150
12 12 12
2 2 2
12 16 16
1 2 4
342 593 923
12 12 12
2 2 2
12 12
1 3
190 329 513
150 200 250
300 400 500
100 125 150
12 12 12
2 2 2
12 12 16
2 4 4
429 650 944
12 12 12
2 2 2
10 10 12
1 2 3
Space (mn)
Total stirrup
2 2 2 2 2 4
mini 50 50 50 50 50 50
maxi 250 250 250 250 250 250
5 5 5
2 2 2
50 50 50
220 250 250
19 23 30
238 239 524
5 5 5
2 2 2
50 50 50
220 250 250
22 27 33
Nb vert. Bar/stir.
20 27 33 20 27 33
Beam # 3 Beam section
Live Load Beam maximum span (metres) 3.00 4.00 5.00 3.00 Office floor 2.50 kN/m2 4.00 5.00 Small industrial floor and storage 5 kN/m2 2.50 3.50 4.50 Horizontal span 3.00 Roof 1kN/m2 4.00 5.00 Domestic floor 2.00 kN/m2
Main reinforcement
Vert. stirrups
Top steel on bearing
Width
Total height
Slab thick.
(mm) 250 250 350 200 350 400
(mm) 300 400 450 350 400 500
(mm) 100 125 150 100 125 150
250 300 400
300 400 500
100 125 150
12 12 12
2 2 2
10 12 16
1 3 4
309 568 940
12 12 12
250 300 350
300 400 500
100 125 150
12 12 12
2 2 2
10 12 16
2 3 4
360 581 884
12 12 12
Dia. 1 Number
Dia.
Number Total
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm) 12 16 16 12 16 16
min. 2 2 4 1 3 4
mm2 393 629 1,072 343 677 1,027
Dia. 1 Number
Dia. 2
Number
Total
Dia.
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm) 10 12 16 10 12 16
min. 2 3 3 1 3 3
mm2 328 524 894 286 565 856
(mm) 5 5 5 5 5 5
2 2 2
10 12 16
1 2 3
257 473 783
2 2 2
10 12 16
1 3 3
Space (mn)
Total stirrup
2 4 4 2 4 4
mini 50 50 50 50 50 50
maxi 220 250 250 250 250 250
5 5 5
2 4 4
50 50 50
220 250 250
19 23 30
300 257 736
5 5 5
2 4 4
50 50 50
220 250 250
22 27 33
Nb vert. Bar/stir.
22 27 33 20 27 33
Beam # 4 Beam section
Live Load Beam maximum span (metres) 3.00 4.00 5.00 3.00 Office floor 2.50 kN/m2 4.00 5.00 Small industrial floor and storage 5 kN/m2 2.50 3.50 4.50 Horizontal span Domestic floor 2.00 kN/m2
Width
Total height
Slab thick.
(mm) 150 200 250 150 200 250
(mm) 350 400 500 350 400 500
(mm) 100 125 150 100 125 150
150 200 250
300 400 500
100 125 150
Main reinforcement Dia.
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm) 10 12 16 12 16 16
min. 1 3 3 1 2 3
mm2 256 461 672 264 477 693
10 12
2 4
223 392 613
12 12 12
2 2 2
Vert. stirrups
Top steel on bearing
Dia. 1 Number
Number Total
Dia. 1 Number
Dia. 2
Number
Total
Dia.
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm)
min.
12 16
2 2
12 16
2 2
mm2 214 384 560 220 398 577
(mm) 5 5 5 5 5 5
10 12
2 3
186 327 511
5 5 5
12 12 12
2 2 2
Space (mn)
2 2 4 2 4 4
mini 50 50 50 50 50 50
maxi 250 250 250 250 250 250
2 2 4
50 50 50
220 250 250
Total stirrup 20 27 33 20 27 33 19 23 30
Table 11 - Typical reinforcement for concrete beams - 2 ways slab and MS steel grade 250
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 118/179 Beam # 5
Liv e Lo ad
Beam m axim u m sp an (m etres)
3.00 4.00 5.00 3.00 O ffic e flo o r 2.50 k N /m 2 4.00 5.00 S m a ll in d u stria l flo o r a n d sto ra g e 5 k N /m 2 2.50 3.50 4.50 Ho rizo n tal sp an 3.00 R oof 1k N /m 2 4.00 5.00 D o m e stic flo o r 1.50 k N /m 2
Beam sectio n W id th T o tal h eigh t (m m ) (m m ) 250 300 300 400 400 500 250 350 350 450 400 500
M ain rein fo rcem en t S lab th ick n ess D ia. N u m b er (m m ) (m m ) m in . 100 4 16 125 8 16 150 S e e ta b le B 7 -4 100 4 16 125 8 16 150 S e e ta b le B 7 -4
T o p steel o n b earin g D ia. N u m b er (m m ) m in . 4 12 4 16 12 16
3 4
V ert. stirru p s D ia. N u m b er (m m ) m in . 20 6 25 6 30 6 20 6 25 6 30 6
250 300 400
300 400 500
100 125 150
4 16 8 16 S e e ta b le B 7 -4
12 16
3 4
8 8 8
20 30 35
250 300 350
300 400 500
100 125 150
4 16 7 16 S e e ta b le B 7 -4
12 16
3 4
6 6 6
15 20 25
Beam # 6 Liv e Lo ad
Beam m axim u m sp an (m etres)
3.00 4.00 5.00 3.00 O ffic e flo o r 2.50 k N /m 2 4.00 5.00 S m a ll in d u stria l flo o r a n d sto ra g e 5 k N /m 2 2.50 3.50 4.50 Ho rizo n tal sp an 3.00 R oof 1k N /m 2 4.00 5.00
D o m e stic flo o r 1.50 k N /m 2
Beam sectio n W id th T o tal h eigh t (m m ) (m m ) 150 350 150 400 200 500 150 350 150 400 200 500
M ain rein fo rcem en t S lab th ick n ess D ia. N u m b er (m m ) (m m ) 100 3 12 125 5 16 150 8 16 100 2 16 125 5 16 150 S e e ta b le B 7 -4
T o p cen ter steel D ia. N u m b er (m m ) 1 12 2 16 4 16 2 12 4 12
V ert. stirru p s D ia. N u m b er (m m ) 20 6 25 6 25 6 20 6 25 6 25 6
150 200 200
300 400 500
100 125 150
16 16 16
2 5 8
12 16 16
1 2 4
6 6 6
20 30 25
150 150 200
300 400 500
100 125 150
16 16 16
2 4 7
12 12 16
1 3 4
6 6 6
15 20 25
Beam # 7 Liv e Lo ad
Beam m axim u m sp an (m etres)
3.00 4.00 5.00 3.00 O ffic e flo o r 2.50 k N /m 2 4.00 5.00 S m a ll in d u stria l flo o r a n d sto ra g e 5 k N /m 2 2.50 3.50 4.50 Ho rizo n tal sp an 3.00 R oof 1k N /m 2 4.00 5.00 D o m e stic flo o r 1.50 k N /m 2
Beam sectio n W id th T o tal h eigh t (m m ) (m m ) 200 300 250 400 300 500 200 350 250 400 300 500
M ain rein fo rcem en t S lab th ick n ess D ia. N u m b er (m m ) (m m ) m in . 100 4 12 125 5 16 150 S e e ta b le B 7 -4 100 4 12 125 6 16 150 S e e ta b le B 7 -4
250 300 350
300 400 500
100 125 150
200 250 300
300 400 500
100 125 150
T o p steel o n b earin g D ia. N u m b er (m m ) m in . 3 12 4 16
V ert. stirru p s D ia. N u m b er (m m ) m in . 20 6 25 6 30 6 20 6 25 6 30 6
12 16
3 5
4 12 5 16 S e e ta b le B 7 -4
12 16
3 4
6 6 6
20 30 35
4 5 7
12 16 16
3 4 6
6 6 6
15 20 25
12 16 16
Beam # 8 Liv e Lo ad
Beam m axim u m sp an (m etres)
3.00 4.00 5.00 3.00 O ffic e flo o r 2.50 k N /m 2 4.00 5.00 S m a ll in d u stria l flo o r a n d sto ra g e 5 k N /m 2 2.50 3.50 4.50 Ho rizo n tal sp an 3.00 R oof 1k N /m 2 4.00 5.00
D o m e stic flo o r 1.50 k N /m 2
Beam sectio n W id th T o tal h eigh t (m m ) (m m ) 200 300 250 400 300 500 200 350 250 400 300 500
S lab th ick n ess (m m ) 100 125 150 100 125 150
M ain rein fo rcem en t D ia. N u m b er (m m ) m in . 2 12 5 12 5 16 2 12 3 16 5 16
T o p steel o n b earin g D ia. N u m b er (m m ) m in . 2 12 4 12 4 16 1 12 4 12 4 16
V ert. stirru p s D ia. N u m b er (m m ) m in . 20 6 25 6 30 6 20 6 25 6 30 6
250 300 350
300 400 500
100 125 150
12 12 16
2 5 5
12 12 16
1 4 4
6 6 6
20 30 35
200 250 300
300 400 500
100 125 150
12 12 16
2 4 4
12 12 16
1 3 4
6 6 6
15 20 25
Table 12 - Typical reinforcement for concrete beams - 1 ways slab and MS steel grade 250
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 119/179 Beam # 1
Beam section
Live Load Beam maximum span (metres) 3.00 4.00 5.00 3.00 Office floor 2.50 kN/m2 4.00 5.00 Small industrial floor and storage 5 kN/m2 2.50 3.50 4.50 Horizontal span 3.00 Roof 1kN/m2 4.00 5.00
Domestic floor 1.50 kN/m2
Top steel on bearing
Main reinforcement
Vert. stirrups
Width
Total height
Slab thick.
Dia. 1 Number
Dia. 2 Number Total
Dia. 1 Number
Dia. 2
Number
Total
Dia.
(mm) 250 250 350 250 300 350
(mm) 300 400 450 300 350 450
(mm) 100 125 150 100 125 150
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm) 12 12 16 12 12 16
min. 2 3 4 2 4 4
mm2 337 534 915 365 677 1,000
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm)
min.
10 16
2 2
12 16
2 2
mm2 187 297 508 203 376 555
(mm) 5 5 5 5 5 5
250 300 350
300 350 400
100 125 150
12 12 12
2 2 2
10 12 16
1 3 4
276 580 1,033
12 12 12
2 2 2
12 16
1 2
153 322 574
250 300 350
300 350 400
100 125 150
12 12 12
2 2 2
12 12 16
1 3 4
323 592 979
12 12 12
2 2 2
12 16
1 2
Nb vert. Bar/stir.
Space (mn)
Total stirrup
2 4 4 2 4 4
mini 50 50 50 49 50 50
maxi 220 250 250 220 250 250
5 5 5
2 4 4
50 50 50
220 250 250
19 23 30
179 440 544
5 5 5
2 4 4
50 50 50
220 250 250
22 27 33
Nb vert. Bar/stir.
22 27 33 22 27 33
Beam # 2 Beam section
Live Load Beam maximum span (metres) 3.00 4.00 5.00 3.00 Office floor 2.50 kN/m2 4.00 5.00 Small industrial floor and storage 5 kN/m2 2.50 3.50 4.50 Horizontal span 3.00 Roof 1kN/m2 4.00 5.00
Domestic floor 1.50 kN/m2
Top steel on bearing
Main reinforcement
Width
Total height
Slab thick.
(mm) 150 200 250 150 200 250
(mm) 350 400 500 350 400 500
(mm) 100 125 150 100 125 150
150 200 250
300 400 500
100 125 150
12 12 12
2 2 2
10 12
2 3
199 350 547
12 12 12
2 2 2
150 200 250
350 400 450
100 125 150
12 12 12
2 2 2
12 12
2 4
213 387 618
12 12 12
2 2 2
Dia. 1 Number
Dia.
Number Total
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm)
min.
12 12
2 4
12 12
2 4
mm2 219 399 578 231 424 616
Vert. stirrups
Dia. 1 Number
Dia. 2
Number
Total
Dia.
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm)
min.
(mm) 5 5 5 5 5 5
Space (mn)
12
1
10 12
1 1
1
111 195 304
5 5 5
2 2 2
50 50 50
220 250 250
19 23 30
1
119 359 343
5 5 5
2 2 2
50 50 48
250 250 250
20 27 34
Nb vert. Bar/stir.
12
12
2 2 2 2 2 4
mini 50 50 50 50 50 50
maxi 250 250 250 250 250 250
Total stirrup
mm2 122 222 321 128 235 342
20 27 33 20 27 33
Beam # 3 Beam section
Live Load Beam maximum span (metres) 3.00 4.00 5.00 3.00 Office floor 2.50 kN/m2 4.00 5.00 Small industrial floor and storage 5 kN/m2 2.50 3.50 4.50 Horizontal span 3.00 Roof 1kN/m2 4.00 5.00
Domestic floor 1.50 kN/m2
Top steel on bearing
Main reinforcement
Width
Total height
Slab thick.
Dia. 1 Number
Dia.
(mm) 250 250 350 250 300 350
(mm) 300 400 450 300 350 450
(mm) 100 125 150 100 125 150
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm)
min.
12 12 10 12 16
2 4 1 2 3
mm2 220 356 607 243 451 667
250 300 350
300 350 400
100 125 150
12 12 12
2 2 2
10 12
2 4
180 386 685
12 12 12
250 300 350
300 350 400
100 125 150
12 12 12
2 2 2
10 12
3 4
210 393 649
12 12 12
Number Total
Vert. stirrups
Dia. 1 Number
Dia. 2
Number
Total
Dia.
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm)
min.
12 12
1 3
12 12
2 4
mm2 183 297 506 202 376 555
(mm) 5 5 5 5 5 5
2 2 2
10 12
2 3
150 321 571
2 2 2
12 12
1 3
Space (mn)
Total stirrup
2 4 4 2 4 4
mini 50 50 50 49 50 50
maxi 220 250 250 220 250 250
5 5 5
2 4 4
50 50 50
220 250 250
19 23 30
175 358 541
5 5 5
2 4 4
50 50 50
220 250 250
22 27 33
Nb vert. Bar/stir.
22 27 33 22 27 33
Beam # 4 Beam section
Live Load Beam maximum span (metres) 3.00 4.00 5.00 3.00 Office floor 2.50 kN/m2 4.00 5.00 Small industrial floor and storage 5 kN/m2 2.50 3.50 4.50 Horizontal span
Domestic floor 1.50 kN/m2
Width
Total height
Slab thick.
(mm) 150 200 250 150 200 250
(mm) 350 400 500 350 400 500
(mm) 100 125 150 100 125 150
150 200 250
300 400 500
100 125 150
Top steel on bearing
Main reinforcement Dia. 1 Number
Dia.
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm)
min.
10 12
1 2
10 12
1 3
mm2 146 265 386 154 282 411
10 12
1 2
133 233 365
12 12 12
2 2 2
Number Total
Vert. stirrups
Dia. 1 Number
Dia. 2
Number
Total
Dia.
(mm) basic bar 2 12 2 12 2 12 2 12 2 12 2 12
(mm)
min.
(mm) 5 5 5 5 5 5 5 5 5
12 12 12
2 2 2
12
1
10 12
1 1
mm2 122 221 321 128 235 342
1
111 195 304
12
Space (mn)
2 2 4 2 4 4
mini 50 50 50 50 50 50
maxi 250 250 250 250 250 250
2 2 4
50 50 50
220 250 250
Total stirrup 20 27 33 20 27 33 19 23 30
Table 13 - Typical reinforcement for concrete beams - 2 ways slab and HR steel grade 420
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 120/179 Beam # 5
Liv e Lo ad
Beam m axim u m sp an (m etres)
3.00 4.00 5.00 3.00 O ffic e flo o r 2.50 k N/m 2 4.00 5.00 Sm a ll ind ustria l flo o r a nd sto ra g e 5 k N/m 2 2.50 3.50 4.50 Ho rizo n tal sp an 3.00 R oof 1k N/m 2 4.00 5.00 D o m e stic flo o r 2.00 k N/m 2
Beam sectio n W id th To tal h eigh t (m m ) (m m ) 250 350 300 450 400 550 250 350 350 450 400 550
S lab th ick n ess (m m ) 100 125 150 100 125 150
Main rein fo rcem en t Dia. Nu m b er (m m ) m in . 3 12 5 16 5 20 3 12 4 16 5 20
T o p steel o n b earin g Dia. Nu m b er (m m ) m in . 1 10 3 12 4 16 1 10 3 12 4 16
Vert. stirru p s Dia. Nu m b er (m m ) m in . 20 6 25 6 30 6 20 6 25 6 30 6
250 300 400
300 450 550
100 125 150
12 16 20
3 4 5
10 12 16
1 3 4
8 8 8
20 30 35
250 300 350
300 450 550
100 125 150
12 16 20
3 3 4
12 16
2 3
6 6 6
15 20 25
Beam # 6 Liv e Lo ad
Beam m axim u m sp an (m etres)
3.00 4.00 5.00 3.00 O ffic e flo o r 2.50 k N/m 2 4.00 5.00 Sm a ll ind ustria l flo o r a nd sto ra g e 5 k N/m 2 2.50 3.50 4.50 Ho rizo n tal sp an 3.00 R oof 1k N/m 2 4.00 5.00 D o m e stic flo o r 2.00 k N/m 2
Beam sectio n W id th To tal h eigh t (m m ) (m m ) 200 350 250 400 300 500 200 350 250 400 300 550
S lab th ick n ess (m m ) 100 125 150 100 125 150
Main rein fo rcem en t Dia. Nu m b er (m m ) 1 10 4 12 4 16 1 10 4 12 4 16
T o p cen ter steel Dia. Nu m b er (m m ) 10 12
1 3
12 12
1 3
Vert. stirru p s Dia. Nu m b er (m m ) 20 6 25 6 25 6 20 6 25 6 25 6
200 250 300
300 400 500
100 125 150
10 12 16
1 4 4
10 12
1 3
6 6 6
20 30 25
200 250 300
300 400 500
100 125 150
10 12 16
1 3 4
10 12
1 2
6 6 6
15 20 25
Beam # 7 Liv e Lo ad
Beam m axim u m sp an (m etres)
3.00 4.00 5.00 3.00 O ffic e flo o r 2.50 k N/m 2 4.00 5.00 Sm a ll ind ustria l flo o r a nd sto ra g e 5 k N/m 2 2.50 3.50 4.50 Ho rizo n tal sp an 3.00 R oof 1k N/m 2 4.00 5.00 D o m e stic flo o r 2.00 k N/m 2
Beam sectio n W id th To tal h eigh t (m m ) (m m ) 200 300 250 400 300 500 200 350 250 400 300 500
S lab th ick n ess (m m ) 100 125 150 100 125 150
Main rein fo rcem en t Dia. Nu m b er (m m ) m in . 2 12 3 16 5 16 2 10 3 16 5 16
T o p steel o n b earin g Dia. Nu m b er (m m ) m in . 1 10 3 12 4 16 1 10 3 16 4 16
Vert. stirru p s Dia. Nu m b er (m m ) m in . 20 6 25 6 30 6 20 6 25 6 30 6
250 300 350
300 400 500
100 125 150
10 16 16
1 3 5
10 12 16
1 3 4
6 6 6
20 30 35
200 250 300
300 400 500
100 125 150
10 12 16
1 3 4
12 16
2 3
6 6 6
15 20 25
Beam # 8 Liv e Lo ad
Beam m axim u m sp an (m etres)
3.00 4.00 5.00 3.00 O ffic e flo o r 2.50 k N/m 2 4.00 5.00 Sm a ll ind ustria l flo o r a nd sto ra g e 5 k N/m 2 2.50 3.50 4.50 Ho rizo n tal sp an 3.00 R oof 1k N/m 2 4.00 5.00 D o m e stic flo o r 2.00 k N/m 2
Beam sectio n W id th To tal h eigh t (m m ) (m m ) 200 300 250 400 300 500 200 350 250 400 300 500
S lab th ick n ess (m m ) 100 125 150 100 125 150
Main rein fo rcem en t Dia. Nu m b er (m m ) m in .
T o p steel o n b earin g Dia. Nu m b er (m m ) m in .
10 12
2 4
10 12
1 3
10 16
3 3
10 12
2 3
Vert. stirru p s Dia. Nu m b er (m m ) m in . 20 6 25 6 30 6 20 6 25 6 30 6
250 300 350
300 400 500
100 125 150
10 12
2 4
10 12
1 3
6 6 6
20 30 35
200 250 300
300 400 500
100 125 150
10 12
2 3
10 12
1 2
6 6 6
15 20 25
Table 14 - Typical reinforcement for concrete beams - 1 ways slab and HR steel grade 420
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
6.1.2.4.2
---
First edition Page 121/179
Form-work
Beams shall be formed by form-work on three sides.
--- The bottom form-work must be rigid enough to support the weight of the structure, the two other sides and the rigours. ---
This bottom form support shall remain in place not less than 10 days minimum.
6.1.2.4.3
Reinforcement
For horizontal and vertical reinforcement see Tables 11, 12, 13, 13 and Figures 40, 51, 59, 66, 67, 68, 69.
6.1.2.4.4
Concrete
Beams shall be filled with 1:1:1 nominal mix (refer to Table 7). The concrete shall be properly compacted and poured at one time.
6.1.3
Framed structure
To be published with next edition.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 122/179
H = Height
H = Height
1 roof load 1 floor load
1 roof load
Fig 52 - Wall height
6.2
Timber
6.2.1
Identification and grade
See characteristics in paragraph "Basic Materials/Timber". 6.2.2
Exterior walls.
Exterior walls of wood-frame construction shall be designed and constructed in accordance with the provisions of this chapter. 6.2.2.1
Stud spacing
In bearing walls, studs, which are not more than 3m in height, shall be spaced not more than is specified in the following Table 15.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 123/179
Table 15 - Maximum stud spacing
Stud size
6.2.2.2
Supporting roof and ceiling only
Supporting on floor, roof and ceiling
Supporting one floor only
50 x 100mm
600mm
400mm
600mm
50 x 150mm
600mm
600mm
600mm
75 x 100mm
600mm
600mm
600mm
Top plate
--- Wood stud walls shall be capped with a double top plate installed to provide overlapping at comers and intersections with bearing partitions (see Figure 54). --- Any joints in top plates shall be offset at least 600 mm. 6.2.2.3
Bearing studs
Where floor or roof framing members is spaced more than 400mm on centre and the bearing studs below are spaced 600mm on centre, such members shall bear within 120mm of the studs beneath.
Exterior or bearing wall
Notch greater than 50%
Top plates
1.5mm metal tie across and to each side of the notch
Pipe
Fig 53 - Top plate framing to accommodate piping
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 124/179
Rafters and ceiling joists or approved roof truss
Top plate
First storey Wall stud See drilling and and notching provisions Floor joist See drilling and and notching provisions
Bottom plate Band joist or blocking
Joist may be cut or notched between these limits
1/3 span
1/3 span
Top plate Joist nailed to stud
Platform framing
Bearing wall
Lap joists 75mm minimum Bottom plate
Sill plate
Joist
Balloon framing
Subfloor Slab on grade foundation
Crawl space or basement foundation
Fig 54 - Typical wall, floor and roof framing
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
6.2.2.4
First edition Page 125/179
Stud length Table 16 - Maximum allowable length of wood studs
Height (m)
On centre spacing 600m
400mm
300mm
200mm
Supporting a roof only >3m
50 x 100mm
50 x 100mm
50 x 100mm
50 x 100mm
3.6m
50 x 150mm
50 x 100mm
50 x 100mm
50 x 100mm
4.2m
50 x 150mm
50 x 150mm
50 x 150mm
50 x 100mm
Supporting one floor and a roof >4.2m
50 x 150mm
50 x 150mm
50 x 150mm
50 x 150mm
Supporting two floors and a roof >4.2m
6.2.2.5
50 x 150mm
50 x 150mm
50 x 150mm
50 x 150mm
Bottom (sole) plate
Studs shall have full bearing on a nominal 40mm or larger plate or sill having a width at least equal to the width of the studs.
6.2.3
Interior load bearing walls
Interior load-bearing walls shall be constructed, framed and fire-stopped as specified for exterior walls.
6.2.4
Interior non-bearing walls
--- Interior non-bearing walls shall be permitted to be constructed with: - 50mm by 75mm studs spaced 600 mm on centre or, when not part of a braced wall line. - 50mm by 100mm flat studs spaced at 400mm on centre. --- Interior non-bearing walls shall be capped with at least a single top plate.
6.2.5
Drilling and notching-studs
--- Any stud in an exterior wall or bearing partition may be cut or notched to a depth not exceeding 25 percent of its width. --- Studs in non bearing partitions may be notched to a depth not to exceed 40 percent of a single stud width. --- Any stud may be bored or drilled, provided that the diameter of the resulting hole is no greater than 40 percent of the stud width, the edge of the hole is no closer than 20mm to the edge of the stud, and the hole is not located in the same section as a cut or notch.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
6.2.5.1
First edition Page 126/179
Drilling and notching of top plate
When piping or ductwork is placed in or partly in an exterior wall or interior load-bearing wall, necessitating a cutting of the top plate by more than 50 percent of its width, a galvanised metal tie not less than 1.37 mm thick (16 gage) and 40mm wide shall be fastened to each plate across and to each side of the opening with not less than six 16d nails.
6.2.6
Headers
For header spans see Tables on floor section. 6.2.6.1
Wood structural panel box headers
Wood structural panel box headers shall be constructed in accordance with following Table 17. Table 17 - Maximum spans for wood structural panel box header
Header construction
Header depth In mm
6.2.6.2
House depth in m 7.5m
8m
8.5m
9m
9.5m
Wood structural panel one side
225mm
1.2m
1.2m
0.9m
0.9m
-
450mm
1.5m
1.5m
1.2m
0.9m
0.9m
Wood structural panel both sides
225mm
2.1m
1.5m
1.5m
1.2m
0.9m
450mm
2.4m
2.4m
2.1m
2.1m
1.8m
Non-bearing walls
--- Load-bearing headers are not required in interior or exterior non-bearing walls. A single flat 50mm by 100mm member may be used as a header in interior or exterior non bearing walls for openings up to 2.4m in width if the vertical distance to the parallel nailing surface above is not more than 600mm. ---
6.2.7
For such non bearing headers, no cripples or blocking are required above the header.
Cripple walls
Foundation cripple walls shall be framed of studs not less in size than the studding above. When exceeding 1.2m in height, such walls shall be framed of studs having the size required for an additional story (see figure 55). 6.2.7.1
Bracing
--- Cripple walls shall be braced with an amount and type of bracing as required for the wall above plus an additional 15 percent of braced wall length or a maximum braced wall panel spacing to 5.5m. --- Cripple walls with a stud height less than 350mm shall be sheathed on at least one side with a wood structural panel that is fastened to both the top and bottom plates, or the cripple walls shall be constructed of solid blocking. Cripple walls shall be supported on continuous foundations.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
6.2.8
First edition Page 127/179
Wall bracing
Braced wall panels, exterior walls, and required interior braced wall lines shall be constructed in accordance with this Section. The braced wall panels in the braced wall lines in each story of the building shall be constructed of a series of one or more braced wall panels. 6.2.8.1
Braced wall lines
--- Braced wall lines shall consist of braced wall panels, which meet the requirements for location, method and amount of bracing specified in following table. --- Braced wall panels which are counted as part of a braced wall line shall be in line, except that offsets out-ofplane of up to 1200mm shall be permitted between adjacent wall panels, provided that the total out-to-out offset dimension in any braced wall line is not more than 2400mm. Braced wall panels shall begin no more than 2400mm from each end of a braced wall line.
Single or double top plate
Fireblock around pipe
Wall sruds
Stagger joints 100mm or use splice plates
Header- see table
Sub floor
Solid blocking
Bottom plate
Jack studs or trimmers
Floor joist Foundation Cripple wall
Sill plate
Foundation wall studs Anchor bolts embedded in foundation
Corner and partition posts
25x 100mm diagonal brace let into studs
Fig 55 - Framing details
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 128/179
Table 18 - Adjustment of bracing amounts for interior braced wall lines according to braced wall line spacing
Braced wall line spacing
Multiply bracing amount by:
Meter
Coefficient
4.5m or less
0.6
6m
0.8
7.5m
1.0
9m
1.2
10.5m
1.4
--- Exterior braced wall lines shall have a braced wall panel located at each end of the braced wall line: 1.
Linear interpolation is permissible.
2. The adjustment is limited to the larger spacing between braced wall lines to either side of an interior braced wall line. 6.2.8.1.1
Sheathing attachment
--- Fastening of braced wall panel sheathing shall be nailed with 8d minimum. --- Adhesive attachment of wall sheathing is not permitted.
6.2.8.2
Braced wall panel construction methods
The construction of braced wall panels shall be in accordance with one of the following methods: a) Nominal 25mm by 100mm continuous diagonal braces let in to the top and bottom plates and the intervening studs or approved metal strap devices installed in accordance with the manufacturer's specifications. - The let-in bracing shall be placed at an angle not more than 60 degrees or less than 45 degrees from the horizontal. b) Wood boards of 16mm net minimum thickness applied diagonally on studs spaced a maximum of 600mm on centre. c) Wood structural panel sheathing with a thickness not less than 8mm for 400mm stud spacing and not less than 10mm for 600mm stud spacing. d) 13mm or 19mm thick structural fibre board sheathing applied vertically on studs spaced a maximum of 400mm on centre.
6.2.8.3
Length of braced panels
For methods 2,3 and 4 above, each braced wall panel shall be at least 1200mm in length, covering a minimum of three stud spaces where studs are spaced 400mm on centre and covering a minimum of two stud spaces where studs are spaced 600mm on centre.
6.2.8.4
Panel joints
--- All vertical joints of panel sheathing shall occur over studs. --- Horizontal joints in braced wall panels shall occur over blocking of a minimum of 40mm thickness.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code 6.2.8.5
First edition Page 129/179
Connection
--- Braced wall panel sole plates shall be fastened to the floor framing and top plates shall be connected to the framing above. --- Sills shall be fastened to the foundation or slab. --- Where joists are perpendicular to the braced wall lines above, blocking shall be provided under and in line with the braced wall panel.
6.2.8.6
Wall anchorage
--- Braced wall line sills shall be anchored to concrete or masonry foundations. --- Plate washers, a minimum 6mm x 50mm x 50mm in size, shall be provided between the foundation sill plate and the nut. 6.2.8.6.1
Interior braced wall panel
Interior braced wall lines shall be fastened to floor and roof framing: 1. Floor joists parallel to the top plate shall be toe nailed to the top plate with at least 8d nails spaced a maximum of 150mm on centre. 2.
6.2.9
Top plate laps shall be face nailed with at least 8-16d nails on each side of the splice
Structure
See figures 7 and 8: a) No timber frame members should be less than 100mm in width. b) At all corners and intersections, uprights should be not less than 100mmx 100mm or 2 members of 50mm x 100mm each bolted together. The posts should be fixed to the sills or floor beams by dowel or metal cleats. c) Intermediate uprights should be not less than 100mm x 50mm and spaced at not more than 600mm. d) The corners of all rooms and intersections should be braced with timber members not less than 50mm x 100mm and shall be jointed to the upright in such a manner as to leave the upright whole. e) The upper sills and wall plates at the outer corners and intersections can be tied with straps at least 225mm x 225mm x 6mm secured with 4 # 10mm diameter coach screws not less than 65mm long. f) Alternatively, bracing may maybe affected by 50mm x 100mm diagonal timber struts in all corners. It is important to have a tight connection between the wall plates and posts. g) The clear height of a wall should not be greater than 3m on the basis of structural calculations showing that the wall framing as designed is adequately supported and can withstand the horizontal imposed loads including wind and earthquakes.
6.2.10
Cladding
a) The cladding of all external walls must be of approved weatherproof material. All cladding must be nailed securely to each framing member. b) Where plaster is used as the cladding, it should consist of not less than two coats applied to metal laths which shall be securely fastened to the weather proof backing. c) The metal laths may consist of expanded metal sheets, "Hirib" or other standard materials. Such material must be used in accordance with the manufacturer's instructions. d) The first or scratch coat of plaster shall be not less than 12mm thick. e) Interior walls may be covered by any approved kind of interior partition boards or with plaster as described above.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 130/179
Steel rafter
Steel haunch
Steel column
25mm thick grout
Steel beam profiles
Anchors
Anchors
Fig 56 - Steel frame typical
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 131/179
Shear connections
Erection seat
Shear splices
Bolted moment splice
Moment splice at ridge (Field bolted)
Stiffener if required
Fig 57 - Beam framing
File # Small building code 2004_draft
Date 1 July, 2004
Shop weld or bolt
Finish col.
Shop weld or bolt
Finish col.
Finish col.
First edition Page 132/179
Finish col.
Trinidad & Tobago Small Building Code
Weld as required
Erection clearance
Erection pin hole (optional)
Finish col.
Finish col.
Shim as required
Fig 58 - Column base plates and connection
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
6.3
First edition Page 133/179
Metal
6.3.1
6.3.1.1
MS beams and profiles
General
For steel framed buildings, two systems are generally used for walls. These are hollow concrete block walls or metal cladding.
6.3.1.1.1
Masonry walls
a) When concrete walls are used, the information given in Section "Masonry block wall" is applicable. There are some minor differences concerning the anchoring of the wall reinforcement. The vertical steel is anchored to the footing in the normal manner and anchored at the top by welding to the longitudinal beam, or fixed to a concrete beam constructed on top of the walls. b) The horizontal reinforcement is welded to the web of the columns. If the columns are encased in concrete the reinforcement can be carried to the face of the steel column. c) Care must be taken to fix these walls to the steel frames so as to provide lateral continuity to the walls and to prevent the wall from collapsing either under the shaking from an earthquake or from the pressures due to hurricane winds. d) It is however, sometimes necessary to install a flexible joint between the block wall and the steel column where the walls have not been used to provide lateral stability. In this event the steel frame must be adequately braced to accommodate the lateral loads without collapse.
6.3.1.1.2 a)
Metal Cladding
Where metal cladding is used, Z-purlins are attached to the columns with suitable fixing.
b) The vertical siding, as the sheeting is then called, is attached to the Z-purlins in the normal manner employed for roofs. Fixings made in the valleys rather than on the crowns would provide greater hurricane resistance. c)
6.4
Care must be taken to prevent leaks.
Mixed construction
--- See Figures 12 for Basic 1 or 2 level house, and 13 for Mixed 1 or 2 level house and typical arrangement. --- Details are on Figures 40 and 51 for typical cross sections.
File # Small building code 2004_draft
Date 1 July, 2004
File # Small building code 2004_draft
Beam #2
Beam #4
Beam #2
Beam #2
Beam #2
Beam #2
Beam #1
Beam #1
Beam #1
Beam #3
Beam #1
Beam #4
Beam #3
Beam #3
Beam #1
Beam #3
Beam #1
Beam #4
Beam #3
Beam #3
Beam #4
Beam #4
Beam #2
Beam #1
Beam #3
Beam #4
Beam #3
Beam #1
Beam #4
Beam #4
Beam #1
Beam #1
Beam #4
Beam #2
Beam #1
Beam #2
2 way supported slab
Beam #1
Beam #3
Beam #1
Beam #1
Beam #1
Beam #3
Beam #3
Beam #4
Beam #3
Beam #4
Beam #6
Beam #8
Beam #6
Beam #6
Beam #6
Beam #6
Beam #5
Beam #5
Beam #6
Beam #6
Beam #5
Beam #6
Beam #8
Beam #7
Beam #7
Beam #8
Beam #8
Beam #7
Beam #8
Beam #8
Beam #7
Beam #7
Beam #8
Beam #8
Beam #7
Beam #8
1 way supported slab (e.g. joists & blocks)
Beam #8
Beam #8
Trinidad & Tobago Small Building Code First edition Page 134/179
Fig 59 - Slabs and beams typical arrangements (1 way or 2 ways)
Date 1 July, 2004
Trinidad & Tobago Small Building Code
7
First edition Page 135/179
Floor systems
7.1
Concrete floor slabs
7.1.1
7.1.1.1
Layout
Slab on grade
For slab on grade (see Figure 35) the following shall be observed: a) The concrete floor shall be a minimum of 100 mm thick and supported on not less than 200 mm of compacted hardcore, gravel or approved granular material. It is recommended that the fill material needed not be more than 900 mm deep and be of well compacted selected granular material. b) Where fills greater than 900 mm are required, the floor shall be constructed as a suspended reinforced concrete slab. This procedure will prevent cracking of the concrete floor slab due to imperfectly compacted fill. c) The finished surface of the floor shall be located not less than 300 mm above finished ground level. On a sloping site, the floor shall be at least 300 mm above the ground at any point at the nearest point relative to the floor.
7.1.1.2
Damp proof course
7.1.1.2.1 A damp proof course shall be provided to prevent rising water through the floor slab and load bearing walls. 7.1.1.2.2 Where polythene is used it shall be at least 0.15 mm thick and shall be laid over the compacted floor foundation. This material shall be used with caution as it easily broken. Laps in the damp proof membrane shall not be less than 150 mm. 7.1.1.2.3 Alternative damp proof course applications: a) Asphalt b) Concrete screed
7.1.1.3
Reinforcement
7.1.1.3.1 The floor slab on grade shall be reinforced with welded wire mesh 150 mm × 150 mm × 3 mm. The mesh shall be located 25 mm below the top surface of the slab and care shall be taken during pouring that this location is maintained. 7.1.1.3.2 The mesh shall be tied to the ground beams where such beams are used. Minimum laps in the mesh shall be 150 mm.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
7.1.1.4
First edition Page 136/179
Suspended Slab
7.1.1.4.1
Solid concrete suspended slab
--- For concrete suspended slab (see Figure 34) the following shall be observed: a) The concrete floor slab shall be a minimum of 125 mm thick and conform to Table 19. b) The maximum span shall conform to Table 19. --- As a protection against flooding, the finished surface of the floor shall be located no less than 300 mm above ground level. On a sloping site, the floor shall be at least 300 mm above the ground at any point at the nearest point relative to the floor. Main reinforcement (2 ways) Dia. Space (mm) (mm) 150 10 150 12 120 12
Top center steel Dia. Spacing (mm) (mm) 250 10 250 12 240 12
Top edge steel Dia. Spacing (mm) (mm) 250 10 250 10 250 10
Maximum span
Slab thickness
(metres)
(mm)
Domestic floor 1.50 kN/m2
3.00 4.00 5.00
100 125 150
Office floor 2.50 kN/m2
3.00 4.00 5.00
100 125 150
10 12 12
150 150 120
10 12 12
250 250 240
10 10 10
250 250 250
100 125 150
10 12 12
120 120 100
10 12 12
240 240 200
10 10 10
250 250 250
100 125 150
10 10 12
200 150 150
10 10 12
250 250 250
10 10 10
250 250 250
Slab location Live Load
Small industrial floor and storage 5 kN/m2 2.50 3.50 4.50
Roof 1kN/m2
Note:
Horizontal span 3.00 4.00 5.00
Steel rods are MS rods and Concrete is Grade "C" (see Table B1) Ratio (Slab Lengh / Slab Width) between 0.8 to 1.25
Slab thickness min 100mm Top center steel lengh = 2 m min. Top edge steel lengh = 1.2m min.
200mm
2000mm min 1000mm min
Table 19 - Typical reinforcement for two way slabs
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 137/179
7.1.1.4.2 Joist and block suspended slab This type of slab, with concrete joists and different types of blocks is very popular world wide because it is easy to realise slab in the housing with a minimum of concrete to be poured on the job site. The dead load of this type of slab depends only of the type of block used.
a)
Joist types
Two types of joist exists : One with heavy pre-stressed concrete that can span 3.6m easily without any temporary support for completion. -
One light concrete bottom base necessary to be supported every 1.20m maximum.
b)
Joist length
The joist length equal span + 100mm min. Different types of support: a)
Concrete or Clay masonry blocks wall
Fig 60 - Joist and blocks slab on masonry wall
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code b)
First edition Page 138/179
Metal beam structure
Fig 61 - Joist and blocks slab on metal structure beam. c)
Block types
Many types of blocks exists for the two series of joists from very light solution with styrofoam to heavy concrete blocks. Blocks can be used independently with the two types of joists.
Fig 62 - Joist and blocks products
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
d)
First edition Page 139/179
Availability of products
For the moment only the 120mm block is available in Trinidad but slab fabricators must develop other thickness as 80mm and more for big span more than 3.5m and right treatment of details (see after).
e)
Slab thickness
--- The slab thickness is composed by the block and the concrete topping. --- Generally the range of blocks available is 80, 120, 150 or 160, 200 and 250mm --- The concrete topping thickness varies from the minimum of 40mm to 50 or 60mm. --- To prevent too much deflection, and without any calculation for justification, the total thickness must be more than span/22.5. Example : span = 4.50m minimum thickness =200mm and can be 160 + 40 or 150 + 50 Note : If services (e.g. electricity conduct) must be installed in the concrete, the minimum topping thickness must be increase by 25mm min. Example : span = 4.50m with electrical conduct in slab minimum thickness 200 + 25 = 225mm composed by 160+65 or 150+75. --- With the use of Clay block n°2 or foam the duct can pass inside the block and the extra thickness is not required.
f)
Reinforcement:
---
Joist reinforcement
The fabricator will reinforce the joists based on your slab drawings and live load required.
---
Joist additional reinforcement
- Joist on edge must be able to absorb a negative moment of 20% of the free span moment and a min of 10mm HT bar x 1.20m is required. - Joist in continuity on internal wall to prevent cracks on top of the slab must be able to absorb a negative moment of 60% of the free span moment and a min of 12mm HT bar x 2.00m is required.
---
Concrete topping reinforcement
The topping shall receive the reinforcement of BRC installed across the joist.
---
Special stiffener
When the slab span is more than 3.60m a central stiffener made with 80mm blocks is required. The reinforcement is done with 2 diameter 10mm in continuity.
--- Slab belt The same reinforcement that other slab apply.
g)
Slab opening
We consider two types of opening :
i.
Small opening less than 1.10m across joist
This opening is contain inside two joists and just a small integrated beam must be made and connected at each end to a minimum of two joists. Only one joist is cut.
ii.
Large opening more than 1.10m wide
In this case several joist are cut and a complete reinforced concrete solution must be done.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 140/179
Fig 63 - Joist and blocks slab with small opening
Fig 64 - Joist and blocks slab with large opening
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
h)
First edition Page 141/179
Balcony
--- The load of the balcony or stair must be compensated with concrete inside the slab and a certain quantity of 80mm blocks used for that. --- This additional concrete will allow to the anchorage of the top reinforcement of the balcony slab even the balcony span in the same direction or across joist.
--- Balcony minimum thickness --- The utile thickness = 1/10 of span or more --- The total thickness = utile thickness + reinforcement coverage (see Table 9)
Fig 65 - Balcony section details Table 20 - Balcony reinforcement Maxi span In m
Min. total thickness In mm
Type of reinforcement HT = high tensile
Top reinforcement Bar Diam In mm
1.00 1.20 1.50
125 145 175
HT HT HT
10mm 10mm 12mm
Min length In m 2.00 2.50 3.00
Nb/m 7 bars/m 9 bars/m 9 bars/m
Long. Reinforcement Bar Nb/m Diam In mm 10 6 10 6 10 6
Important note : When heavy concrete stair is connected and supported by balcony, the above table not apply and Engineer is required.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 142/179
Basic 6mm dia. stirrup and 4x12mm bar
Additionnal stirrup if 3 bars to be maintained Additionnal bar to be maintained
9 rods
7 bars as Table 8 rods
6 bars as Table 7 rods
5 bars as Table 6 rods
4 bars as Table 5 rods
3 bars as Table 4 rods
or
3 rods 2 rods
2 bars as Table 1 bar as Table no bar added as Table Additionnal bar See tables
Fig 66 - Beam reinforcement - Typical arrangement Mild Steel
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 143/179
Basic 6mm dia. stirrup and 4x10mm bar
Additionnal stirrup if 3 bars to be maintained Additionnal bar to be maintained
7 rods
5 bars as Table 6 rods
4 bars as Table 5 rods
3 bars as Table 4 rods
or
2 bars as Table
3 rods
1 bar as Table
2 rods
no bar added as Table Additionnal bar See tables Fig 67 - Beam reinforcement - Typical arrangement HR Steel
File # Small building code 2004_draft
Date 1 July, 2004
First edition Page 144/179
Main reinforcement
Width
Assembly rods
Total height
Type of stirrup
Trinidad & Tobago Small Building Code
Rod details
Span Total number stirrups max. 200mm
Column 250mm min
min 75mm Width
Midle top reinforcement
45°
minimum lap see table B-3
Fig 68 - Concrete beams (Middle & Side)
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 145/179
Total height
Width
Column 250mm min Width
Fig 69 - Beam sections
7.1.1.4.3
Reinforcement
The minimum requirement for the reinforcement shall conform to Table 19.
7.1.2
Finishing
The slab shall be floated immediately after pouring as this produces a durable surface. Alternatively, a sand cement screed not less than 20 mm thick may be applied to roughened surface of the concrete. The surface shall be cleaned and washed before applying the screed. A screed of proportions of 1 part cement to 4 parts sand (by volume) is acceptable.
7.1.3
Services
All pipes and conduits for services shall be laid and arranged so that the required concrete cover to the reinforcement is maintained. Note: Most structures within the scope of these guidelines would have floor slabs on compacted granular material; but on sloping sites, floor slabs may have to be suspended. The reinforcement set out above will provide a safe suspended floor or roof. Professional assistance should be sought on the size and placement of reinforcement for situations other than those described.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 146/179
Botom wall plate Studs
Subfloor or floor sheating
Sill plates
Optional finish floor
Band, rim or header joist
Joists Wood structural panel Bridging
Solid blocking
Sill plate
Foundation Double joist under bearing partitions pipe in partition
Fig 70 - Timber flooring & supports
7.2
Timber
7.2.1
Identification & Grade
See characteristics in paragraph "Basic Materials/Timber".
7.2.2 7.2.2.1
General Design and construction
Floors shall be designed and constructed in accordance with the provisions of this chapter and Figure 70.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
7.2.2.2
First edition Page 147/179
Allowable joist spans
Spans for floor joists shall be in accordance with Table 21.
Table 21 - Floor joist span for common lumber species Joist spacing
Dead load = 1kN/m2 and Live load 1.5kN/m2 50x150mm
50x200mm
50x250mm
50x300mm
Maximum floor joist spans in metre
7.2.2.3
300mm
3.3m
4.2m
5.1m
6m
400mm
3m
3.6m
4.5m
5.2m
500mm
2.6m
3.3m
4m
4.6m
600mm
2.3m
3m
3.6m
4.2m
Joists under bearing partitions
Joists under parallel bearing partitions shall be doubled or a beam of adequate size to support the load shall be provided. Double joists, which are separated to permit the installation of piping or vents, shall be full depth solid blocked with lumber not less than 50mm in nominal thickness spaced not more than 1200mm on centre.
7.2.2.4
Allowable header spans
The allowable spans of headers shall not exceed the values set forth in Tables 22 and 23.
Table 22 - Header spans for exterior bearing walls Headers supporting
Number and sizes of header
Building width in metre < or = 6m
6m <
< 8.5m
8.5m <
< 11m
Maximum header span in metre Roof and ceiling
Roof, ceiling & 1 centre bearing floor Roof, ceiling & 1 clear span floor
2 - 50x100mm
1m
0.9m
0.8m
2 – 50x150mm
1.6m
1.4m
1.2m
2 – 50x200mm
1.9m
1.7m
1.6m
2 - 50x100mm
0.9m
0.8m
0.7m
2 – 50x150mm
1.3m
1.2m
1.1m
2 – 50x200mm
1.7m
1.5m
1.35m
2 - 50x100mm
0.8m
0.7m
0.6m
2 – 50x150mm
1.15m
1.1m
0.9m
2 – 50x200mm
1.5m
1.3m
1.15m
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 148/179
Table 23 - Header spans for interior bearing walls Headers and girders supporting
Building width in metre
Number and sizes of header
< or = 6m
6m < 8.5m
<
8.5m < 11m
<
Maximum header span in metre One floor only
2 - 50x100mm
0.95m
0.8m
0.7m
One floor only
2 – 50x150mm
1.35m
1.15m
1.05m
One floor only
2 – 50x200mm
1.75m
1.5m
1.35m
One floor only
2 – 50x250mm
2.1m
1.8m
1.55m
One floor only
2 – 50x300mm
2.4m
2.1m
1.9m
L no notches permited
L/3
D/6 maxi
D/6 maxi
D
L/3
D/4 maxi
D
D/4 maxi
Floor joist - center cuts
D/3 maxi
Floor joist - end cuts
D
maxi D from support
50mm mini
D
50mm mini
Rafter/ceiling joists
D/ 3
m ax i
Drilling
Fig 71 - Joist cutting, notching and drilling
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
7.2.2.5
First edition Page 149/179
Bearing
The ends of each joist beam or header shall have not less than 50mm of bearing on wood or metal and not less than 75mm on masonry or concrete.
7.2.2.5.1
Floor systems
Joists framing from opposite sides over a bearing support shall lap a minimum of 75 mm and shall be nailed together. A wood or metal splice with strength equal to or greater than that provided by the nailed lap is permitted.
7.2.2.5.2
Joist framing
Joists framing into the side of a wood header shall be supported by approved framing anchors or on ledger strips not less than nominal 50mm by 50mm.
7.2.2.6
Lateral restraint at supports
Joists shall be supported laterally at the ends by full-depth solid blocking not less than 50mm nominal in thickness; or by attachment to a header, band or rim joist, or to an adjoining stud; or shall be otherwise provided with lateral support to prevent rotation.
7.2.2.6.1
Bridging
Joists exceeding a nominal 50mm x 150mm shall be supported laterally by solid blocking, diagonal bridging (wood or metal), or a continuous 25mm by 75mm strip nailed across the bottom of joists perpendicular to joists at intervals not exceeding 2400mm.
7.2.2.7
Drilling and notching
Structural floor members shall not be cut, bored or notched in excess of the limitations specified in this section. See Figure 71.
7.2.2.7.1
Engineered wood products
Cuts, notches and holes bored in trusses, laminated veneer lumber, glue-laminated members or I-joists are not permitted unless the effect of such penetrations are specifically considered in the design of the member.
7.2.2.8
Fastening
Floor framing shall be nailed or screwed. Where posts and beam or header construction is used to support floor framing, positive connections shall be provided to ensure against uplift and lateral displacement.
7.2.2.9
Framing of openings
--- Openings in floor framing shall be framed with a header and trimmer joists. --- When the header joist span does not exceed 1200mm, the header joist may be a single member the same size as the floor joist. Single trimmer joists may be used to carry a single header joist that is located within 900mm of the trimmer joist bearing. --- When the header joist span exceeds 1200mm, the trimmer joists and the header joist shall be doubled and of sufficient cross section to support the floor joists framing into the header. Approved hangers shall be used for the header joist to trimmer joist connections when the header joist span exceeds 1800mm.
7.2.2.10
Wood trusses
7.2.2.10.1 Design ---
Wood trusses shall be designed in accordance with approved engineering practice.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 150/179
--- The design and manufacture of metal plate connected wood trusses shall comply with ANSI/TPI 1, National Design Standard for Metal Plate Connected Wood Truss Construction.
7.2.2.10.2 Bracing Trusses shall be braced to prevent rotation and provide lateral stability in accordance with the requirements specified in the construction documents for the building and on the individual truss design drawings.
7.2.2.10.3 Alterations to trusses --- Truss members and components shall not be cut, notched, spliced or otherwise altered in any way without the approval of a registered design professional. --- Alterations resulting in the addition of load (e.g. HVAC equipment, water heater, water tank etc.), that exceeds the design load for the truss shall not be permitted without verification that the truss is capable of supporting the additional loading.
7.2.3
7.2.3.1
Floor sheathing
Lumber sheathing
--- Maximum allowable spans for lumber used, as floor sheathing shall conform to the following Table 24.
Table 24 - Minimum thickness of floor sheathing Joist or beam spacing in mm
Minimum net thickness Perpendicular to joist
Diagonal to joist
400mm
16mm
16mm
600mm
19mm
19mm
--- Plywood continuous over two or more spans and face grain perpendicular to supports. Unsupported edges shall be tongue and grove or blocked.
7.2.3.1.1
End joints
End joints in lumber used, as flooring shall occur over supports.
7.2.3.2
Wood structural panel sheathing
7.2.3.2.1
Identification and grade
Wood structural panel sheathing used for structural purposes shall be identified by a grade mark of certificate of inspection issued by an approved agency.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
7.2.3.2.2
First edition Page 151/179
Wood structural panel
--- Where used, wood structural panels shall be of one of the grades specified in Table 24. --- When sanded plywood is used as combination sub-floor underlay, the grade shall be as specified in Table 24.
7.2.3.3
Particleboard
7.2.3.3.1
Identification and grade
Particleboard shall conform to ANSI A208.1 and shall be so identified by a grade mark or certificate of inspection issued by an approved agency.
7.2.3.3.2
Particle board panel
Where used, particleboard panels shall be of one of the grades specified in Table 24.
7.3
Metal
7.3.1
MS steel beam
MS steel beam structure shall be engineered based on values given by the Design criteria and other characteristics of this code by a recognised registered professional.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 152/179
ridge board
hip rafter
jack rafter
maxim
um s e e table s
facia board
facia board
hip rafter r.c. ring beam
jack rafter
ridge board
rafters
Fig 72 - Typical hip roof construction
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
8
First edition Page 153/179
Roof assemblies
8.1
Roof structure
8.1.1
Concrete roof structure
Ditto paragraph “Concrete floor slabs".
8.1.2
8.1.2.1
Timber
Layout
8.1.2.1.1
Roofs are generally constructed as one of three common types. These are:
a) hip roofs; b) gable roofs; or c) mono roof. (lean-to)
8.1.2.1.2
The gable roof consists of a structural frame made up of a ridge board and (with) rafters.
8.1.2.1.3 The minimum sizes of roof members shall be 25 mm × 150 mm for the ridge board and 50 mm × 100 mm for the rafters at 800 mm between centres. The same size rafters shall be used for mono-pitched (shed) roofs. 8.1.2.1.4
In the case of the hip roof, hip rafters are introduced into the structural frame as shown in Figure 72.
8.1.2.1.5 The minimum size of the hip rafters shall be 50 mm × 150 mm. Table 25 gives rafter sizes of main members constructed of pitch pine. 8.1.2.1.6 The use of timber other than pitch pine at the minimum recommended sizes for pitch pine is acceptable only if it is a stronger timber. Professional advice shall be sought if smaller sizes are used for stronger timber or if weaker timber is used. (See Table 6 for specifying different types of timber). 8.1.2.1.7 The timber roof ceiling is generally constructed using 25 mm × 150 mm tongue-and-groove boarding, 16 mm plywood or other patented boarding. 8.1.2.1.8 Sheeting may be replaced by a secondary frame of 50 mm × 50 mm or 50 mm × 100 mm battens fixed to the rafters.
8.1.2.2
Fixings
8.1.2.2.1 The rafters shall be securely fixed to the ring beam at the top of the walls on a wall plate and to the ridge board at the crown of the roof. 8.1.2.2.2 The use of patented hurricane clips (rafter ties) for fixing rafters to plates; purlins and ridge boards shall be used.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
Rafter spacing
First edition Page 154/179
Dead load = 0.50 kN/m2 Light roof with galvanized sheeting
Solutions 50x100
50x150
Calculation based on minimum wood stress of Maximum length of wood
50x200
50x250
7,500.00 kN/m2 6.00 m
Dead load = 1.00 kN/m2 Semi light roof with suspended ceiling and asphalt shingle
Dead load = 1.50 kN/m3 Roof with ceiling and ordinary clay or cement tiles
50x100
50x100
50x150
50x200
50x250
minimum calculated span authorised more than
50x150
50x200
50x250
1.50 m
Rough material Solution 1 400mm 600mm 800mm
minimum span span span
live load = 0.60 kN/m2 3.40 5.10 2.80 4.10 2.40 3.60
5.50 4.80
Solution 2 400mm 600mm 800mm
normal span span span
live or climatic load = 1 kN/m2 2.90 4.30 2.40 3.50 2.00 3.10
5.80 4.70 4.10
Solution 3 400mm 600mm 800mm
span span span
climatic load = 1.5 kN/m2 2.50 3.80 2.00 3.10 1.80 2.70
5.00 4.10 3.50
How to use the table a) b) c)
2.80 2.30 2.00
4.20 3.40 3.00
5.60 4.60 4.00
5.70 4.90
2.40 2.00 1.70
3.70 3.00 2.60
4.90 4.00 3.50
5.00 4.30
5.90 5.10
2.50 2.00 1.80
3.80 3.10 2.70
5.00 4.10 3.50
5.10 4.40
2.20 1.80 1.60
3.40 2.70 2.40
4.50 3.70 3.20
5.60 4.60 4.00
5.10 4.40
2.20 1.80 1.60
3.40 2.70 2.40
4.50 3.70 3.20
5.60 4.60 4.00
2.00 1.70
3.10 2.50 2.20
4.10 3.30 2.90
5.10 4.20 3.60
choose the coloumns with the type of roof (dead load) choose the lignes with the type of exposure (climatic load) and type of wood (rough or dressed) with the span required choose the righ solution (rafter spacing and size) rafter spacing in the left coloumn size on top of the table
Table 25 - Maximum roof span for rafter (first part) File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
Rafter spacing
First edition Page 155/179
Dead load = 0.50 kN/m2 Light roof with galvanized sheeting
Solutions 50x100
50x150
Calculation based on minimum wood stress of Maximum length of wood Dressed material exact sizes Solution 11 400mm 600mm 800mm
50x250
7,500.00 kN/m2 6.00 m
50x100
50x100
50x150
50x200
50x250
minimum calculated span authorised more than
38x138
38x188
38x238
live load = 0.60 kN/m2 2.60 4.10 2.10 3.30 1.80 2.90
5.50 4.50 3.90
5.70 4.90
Solution 12 400mm span 600mm span 800mm span
live or climatic load = 1.00 kN/m2 2.20 3.50 1.80 2.80 1.60 2.50
4.70 3.90 3.30
Solution 13 400mm span 600mm span 800mm span
climatic load = 1.50 kN/m2 1.90 3.00 1.60 2.50 2.10
4.10 3.30 2.90
How to use the table a) b) c)
Dead load = 1.50 kN/m3 Roof with ceiling and ordinary clay or cement tiles 50x150
50x200
50x250
38x188
38x238
1.50 m
loss of 12mm in all direction in rough sizing of the material 38x88
minimum span span span
50x200
Dead load = 1.00 kN/m2 Semi light roof with suspended ceiling and asphalt shingle
38x88
38x138
38x188
38x238
38x88
38x138
2.10 1.80 1.50
3.40 2.70 2.40
4.60 3.70 3.20
5.80 4.70 4.10
1.90 1.50
2.90 2.40 2.10
4.00 3.30 2.80
5.10 4.10 3.60
6.00 4.90 4.20
1.90 1.60
3.00 2.50 2.10
4.10 3.30 2.90
5.20 4.20 3.70
1.70
2.70 2.20 1.90
3.70 3.00 2.60
4.60 3.80 3.30
5.20 4.20 3.70
1.70 1.40
2.70 2.20 1.90
3.70 3.00 2.60
4.60 3.80 3.30
1.60
2.50 2.00 1.70
3.30 2.70 2.40
4.20 3.50 3.00
choose the coloumns with the type of roof (dead load) choose the lignes with the type of exposure (climatic load) and type of wood (rough or dressed) with the span required choose the righ solution (rafter spacing and size) rafter spacing in the left coloumn size on top of the table
Table 25 - Maximum roof span for rafter (second part)
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code Rafter or truss spacing
First edition Page 156/179 Dead load = 0.50 kN/m2 Light roof with galvanized sheeting
Solutions 100x25
50x50
100x50
50x100
50x150
Calculation based on minimum wood stress of 7,500.00 kN/m2 Maximum span of wood 30 times wood height (to prevent flexion) 750 1500 1500 3000 Rough material Maximum space for battens Solution 1 400mm 600mm 800mm 1000mm 1250mm 1500mm 1800mm 2000mm 2500mm 3000mm 4000mm
minimum live load = 0.60 kN/m2 batten space batten space batten space 0.90 1.80 batten space 0.60 1.10 batten space 0.40 0.70 batten space 0.50 batten space batten space batten space batten space batten space
Solution 2 400mm 600mm 800mm 1000mm 1250mm 1500mm 1800mm 2000mm 2500mm 3000mm 4000mm
normal live or climatic load = 1 kN/m2 batten space batten space 1.20 batten space 0.70 1.30 batten space 0.80 1.70 batten space 0.50 1.10 batten space 0.40 0.70 batten space batten space batten space batten space batten space
Solution 3 400mm 600mm 800mm 1000mm 1250mm 1500mm 1800mm 2000mm 2500mm 3000mm
exposed climatic load = 1.5 kN/m2 batten space 2.00 batten space 0.90 1.70 batten space 0.50 1.00 batten space 0.60 batten space 0.40 batten space 0.30 batten space batten space batten space batten space
How to use the table a) b) c)
4500
100X150
50x25
4500
Maximum space for purlins
100x25
750
750
1.10 0.60
1.50 1.00 3.20 2.60 1.60 1.10 0.60
2.30 1.90 1.20 0.80
1.60 1.10 0.80
2.50 1.70 1.40 0.90
1500
1500
1.20 0.80 0.50 0.30
0.90 0.50
1.00 0.60 0.40 0.30
0.70 0.40
50x100
3000
50x150
4500
100X150
4500
Maximum space for purlins
50x25
100x25
750
1.60 1.00 0.70
2.00 1.40 1.00 0.80
2.20 1.80 1.10 0.80
1.60 1.10 0.80 0.60
2.50 1.70 1.40 0.90 0.60
3.50 2.80 1.80 1.30
1.00 0.60 0.40
1.30 0.90
2.00 1.40 1.10
1500
50x100
1500
0.80 0.50
0.90 0.60 0.40 0.30
0.70 0.40
0.80 0.50 0.30
4.00 2.80 2.30 1.40 1.00
1.30 0.60 0.30
1.20 0.70 0.40 0.30
3000
50x150
100X150
4500
1.20 0.80 0.50
1.00 0.60 0.40
1.30 0.80 0.50 0.40
1.50 1.10 0.70 0.60
1.30 0.90 0.60
2.60 1.70 1.10 0.70 0.50
2.40 1.70 1.30 0.90 0.60
2.00 1.40 1.10 0.70
2.40 1.70 1.20 0.90
choose the columns with the type of roof (dead load) choose the paragraph with the type of exposure (climatic load) and type of space between rafters or trusses with the span required choose the righ solution (batten spacing and sizes)
Table 26 - Maximum roof span for battens and joist
File # Small building code 2004_draft
4500
Maximum space for purlins
3.50 2.80 1.80 1.30 0.70
0.70 0.30 0.80 0.50 0.30
100x50
4.30 3.50 2.30 1.60 0.90
0.30 0.20 1.30 0.80 0.60
750
50x50
Maximum space for battens
0.40 0.20
3.80 2.40 1.70 0.90
0.80 0.30 0.20 1.30 0.80 0.60
100x50
5.10 3.30 2.30 1.30
1.00 0.40 0.20 2.10 1.50 1.00 0.80
50x50
Maximum space for battens 1.20 0.50 0.30
1.40 1.10 0.70
Dead load = 1.50 kN/m3 Roof with ceiling and ordinary clay or cement tiles
Dead load = 1.00 kN/m2 Semi light roof with suspended ceiling and asphalt shingle
Date 1 July, 2004
3.30 2.70 1.70 1.20 0.70
4.00 2.80 2.30 1.40 1.00
3.30 2.30 1.90 1.20 0.80
Trinidad & Tobago Small Building Code
8.1.2.2.3
First edition Page 157/179
Plywood decking shall be fastened to the purlins or rafters at a spacing of not less than 600 mm.
8.1.2.2.4 Where timber boards are used as decking, the timber shall be secured at each purlin by at least two galvanised head clout nails at least 40 mm long.
Solution 2 Metal sheet (see paragraph " Metal sheeting" for decking)
Solution 3 Asphalt shingle
Solution 4 Clay or concrete tile
Underlay
Decking (plywood or closeboard)
Solution 1 Metal sheet (see paragraph " Metal sheeting" for purlins or battens spacing )
Decking (plywood or closeboard) 16mm thickness
g cin spa
OK
Exception C replace Z
Sag steel rod @ 10 or 12 mm diam
Fixation type 1 (slope 2m)
Fig 73 - Z purlin details
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 158/179
Solution 2 Metal sheet (see paragraph "Metal sheeting" for decking)
Solution 3 Asphalt shingle
Solution 4 Clay or concrete tile
Underlay
Decking (plywood or closeboard)
Decking (plywood or closeboard) 16mm thickness
Solution 1 Metal sheet (see paragraph "Metal sheeting" for purlins or battens spacing)
Fixation type 2 Type ridge Slope
Rafter
Horiz. span
Spacing 400mm or 600mm or 800mm Fixation type 1 On ring beam Fig 74 - Z or C steel profile used as rafter
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 159/179
Beam type 1
Wall or concrete beam Beam section Slope in °
Horizontal beam span
rof ile
3 d minimum
Hp
2 H profile
Cantilever
Typical assembly for beam more than 150mm
Beam type 2
Slope in °
Horizontal beam span Cantilever
Wall or concrete beam
Typical combinations
Fig 75 - Beam framing
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 160/179 Beam type 1
Base on design criteria of Trinidad & Tobago Building Code
W eight in kg/m
Frame spacing in meter Horizontal beam span in meter S 3x5.7 (75mm x 60mm)
8.48
S 4x7.7 (102mm x 68mm)
11.45
S 5x10 (127mm x 76mm)
14.87
W 4x13 (106mm x 103mm)
19.33
W 6x12 (153mm x 102mm)
17.85
W 8x13 (204mm x 102mm)
19.33
Horizontal beam span in meter S 3x5.7 (75mm x 60mm)
8.48
S 4x7.7 (102mm x 68mm)
11.45
S 5x10 (127mm x 76mm)
14.87
W 4x13 (106mm x 103mm)
19.33
W 6x12 (153mm x 102mm)
17.85
W 8x13 (204mm x 102mm)
19.33
Horizontal beam span in meter
Solution 1
Solution 2 Galvanized 0.5mm
4.80
Horizontal beam span in meter
Solution 3
6.00
6.00
Yes
6.00
5.40
5.40
5.40
5.40
5.40
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
6.00
6.00
6.00
6.00
Yes
Yes
Yes
Yes Yes Yes
Yes
6.00
6.00
6.00
6.00
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes Yes Yes
Yes Yes Yes
Yes
175 N/mm2 Yes
Table 27 - MS beam type 1
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 161/179
Beam type 2 Base on design criteria of Trinidad & Tobago Building Code
Weight in kg/m
Frame spacing in meter Horizontal beam span in meter S 4x7.7 (102mm x 68mm) S 5x10 (127mm x 76mm) W 4x13 (106mm x 103mm) W 6x12 (153mm x 102mm) W 8x13 (204mm x 102mm) W10x15 (254mm x 102mm)
S 5x10 (127mm x 76mm) W 4x13 (106mm x 103mm) W 6x12 (153mm x 102mm) W 8x13 (204mm x 102mm) W10x15 (254mm x 102mm)
W 4x13 (106mm x 103mm) W 6x12 (153mm x 102mm) W 8x13 (204mm x 102mm) W10x15 (254mm x 102mm)
W 4x13 (106mm x 103mm) W 6x12 (153mm x 102mm) W 8x13 (204mm x 102mm) W10x15 (254mm x 102mm)
Note: Maximum strengh limited to Acceptable solution for profile
3.60
4.20
3.00
3.60
4.20
3.00
3.60
4.20
4.80
4.80
4.80
4.80
4.80
4.80
4.80
4.80
4.80
4.80
4.80
4.80
Asphalt shingle
Concrete or clay tile
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes Yes
Yes
5.40
5.40
5.40
5.40
5.40
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
5.40
5.40
5.40
5.40
5.40
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
5.40
5.40
Yes Yes Yes
Yes
Yes
Yes
Yes Yes
6.00
6.00
Yes Yes
6.00
6.00
6.00
6.00
6.00
Yes
Yes
Yes
Yes
Yes
Yes
6.00
6.00
Yes
Yes
6.00
6.00
Yes Yes Yes
Yes Yes
Yes
Yes
Yes
19.33 17.85 19.33 22.31
6.60
6.60
6.60
Yes
Yes
Yes
Yes
Yes
6.60
6.60
6.60
Yes
Yes
6.60
6.60
6.60
Yes Yes
Yes
6.60
6.60
Yes Yes
7.20
7.20
Yes
Yes
19.33 17.85 19.33 22.31
Yes
7.20
19.33 17.85 19.33 22.31
7.80
Yes Yes
7.20
7.20
Yes
7.20
7.20
Yes
Yes
Yes
Yes
Yes
Yes
Yes
7.20
7.20
7.20
7.20
7.20
Yes Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
7.80
7.80
7.80
7.80
7.80
7.80
7.80
7.80
7.80
Yes
Yes Yes
Yes
8.40
8.40
8.40
8.40
Yes
7.80
Horizontal beam span in meter W 4x13 (106mm x 103mm) W 6x12 (153mm x 102mm) W 8x13 (204mm x 102mm) W10x15 (254mm x 102mm)
3.00
6.60
Horizontal beam span in meter W 4x13 (106mm x 103mm) W 6x12 (153mm x 102mm) W 8x13 (204mm x 102mm) W10x15 (254mm x 102mm)
Galvanized 0.5mm
11.45 14.87 19.33 17.85 19.33 22.31
Horizontal beam span in meter S 5x10 (127mm x 76mm) W 4x13 (106mm x 103mm) W 6x12 (153mm x 102mm) W 8x13 (204mm x 102mm) W10x15 (254mm x 102mm)
Solution 1
7.80
Yes Yes
Yes Yes
8.40
8.40
Yes
Yes
19.33 17.85 19.33 22.31
Yes
Yes
8.40
8.40
8.40
8.40
Yes
8.40
8.40
Yes Yes
Yes
Yes
Yes
175 N/mm2 for limitation of deflection to 1/240 Yes
Table 28 - MS beam type 2
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
8.1.3
8.1.3.1
First edition Page 162/179
Metal
MS steel beam
8.1.3.1.1
Roof structure
--- See Figure 75 for details and combinations --- See Tables 27 MS beam type 1 and 28 MS beam type 2 for recommended sections.
8.1.3.2
Cold formed steel
Cold formed steel is composed of galvanised steel sheet 1mm to 1.5mm thickness for C, U and Z sections roll formed profiles.
8.1.3.2.1
Cold formed steel fastening
Cold formed steel must be fastened be self tapping screws or bolt and nuts.
Welding is not allowed.
8.1.3.2.2
Roof structure
--- Cold formed steel shall be used for purling and rafter as shown in Figures 73 and 74. --- See Tables 29 & 30 - Z purlins and 31 & 32 - Z or C rafters for recommended sections.
File # Small building code 2004_draft
Date 1 July, 2004
Trinidad & Tobago Small Building Code
First edition Page 163/179 Metal steel Z purlins (20G)
Base on design criteria of Trinidad & Tobago Building Code
Sol 1
Sol 2
Sol 3
Sol 4
Galvanized >0.5mm
Galvanized 0.5mm
Galvanized 0.5mm Galvanized 0.5mm Galvanized
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