Work Below Lowest Floor Finish (Wblff)

WORK BELOW LOWEST FLOOR FINISH (WBLFF)

WBLFF/ SUBSTRUCTURE - COMPONENTS 1. Column bases/Pad Footings/Strip Footing/Pile Caps 2. Column Stumps 3. Ground Beam 4. Bed/Slab

Excavation (m3) Filling (m3) Disposal (m3) Hardcore (m2/m3)

Excavation (m3) Disposal (m3) Filling (m3)

Blinding (m3) Damp-proof membrane (m2) Bed/Slab

Concrete (m3) Formwork (m/m2)

Pad/Strip footing/ Pile caps

Reinforcement (kg)

Excavation (m3)

WBLFF/ Substructure

Concrete (m3) Formwork (m/m2) Reinforcement (kg)

Filling (m3) Disposal (m3)

Ground Beam

Column Stumps

Concrete (m3)

Blinding (m3) Concrete (m3) Formwork (m/m2)

Formwork (m/m2) Reinforcement (kg)

CONCRETE WORK 

F.1  –  GENERALLY 

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F.3  –  CONCRETE CATEGORIES

Plain in-situ concrete/ Reinforced in-situ concrete

2. Foundation in trenches

Grade concrete

5. Ground Beam

F.2.1  –  THICKNESS CATEGORIES 

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Not exceeding 100mm

3. Isolated foundation bases

7. Pile caps 8. Beds

100mm – 150mm

9. Suspended slabs

150mm – 300mm

15. Isolated columns

exceeding 300mm

16. Steps/staircase

CONCRETE WORKS 

Example:

Plain In-Situ Concrete Grade 7 as specified; blinding screed; laid on earth or hardcore Under pile caps/pad footings/ground beam/grd. Floor slab

Reinforced In-Situ Concrete Grade …… as specified In foundation in trenches In isolated foundation bases to columns (In No………) In ground beams

REINFORCEMENT 

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F.8.4 - CLASSIFICATION 

In foundation (bases, ground beam & pile cap)

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In ground slabs (beds)

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In isolated column (stump)

F.8.5 - CATEGORIES 

Straight and bend bars

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Curved bars

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Link, stirrups, binders and the like

Straight and bend bars (4 Y12) Link, stirrups, binders and the like (28 R8 - 250) Width  –  Conc. Covers (40mm) + Hooks (24 x diameter of bar)

REINFORCEMENT 

Example:

Reinforcement bars; hot rolled plain round mild steel Reinforcement bars; hot rolled deformed high tensile steel In foundation in trenches In isolated foundations In ground beams In pile caps In pad footings

FORMWORKS 

F.10.1  –  CATEGORIES F.11.1 - Formwork to edges & faces of: 

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Foundations and beds (footings, pile caps bases, ground beams)

HEIGHT CATEGORIES (for height n.e. 1.00m) 

Not exceeding 250mm high 250mm – 500mm high 500mm – 1.00m high

FORMWORKS 

Example:

Class F1 formwork as specified to foundation and beds To edges & faces of pile caps To edges & faces of pad footings To edges & faces of strip footings To edges of beds To edges of slabs To ground beams To sides of column stumps

HARDCORE 

D.23 – Classification of materials - Material arising from excavation

FILLING

- Material arising from excavation to be selected and treated

Hardcore of clean hard broken stones to be obtained off site at contractor own source

- Material to be obtained off site at contractor own source 

D.26 – Filling to make up levels >250mm shall be given in m3 250mm shall be given in m3 stating

To make up levels not exceeding 250mm thick; average 250mm thick To make up levels over 250mm thick  To make up l evels over 250mm thick; depositing in layers; ...mm maximum thickness

DAMP PROOF MEMBRANE 

K.1 – Classification of Work  a. Damp proofing & tanking b. Flooring & underlay c. Paving d. Roofing

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K.2 – Measurement 1. Description shall include: - Kind & quality of material - Thickness & no. of coats & layers - Nature of base - Surface treatment 2. No deduction shall be made for voids

3. Covering > 300mm wide shall be in m2 < 300mm wide shall be in m (stating the width in stages of 150mm) Classification – a. Flat coverings n.e. 10° (horizontal) b. Sloping covering over 10° but n.e. 45° (horizontal) c. Sloping covering over 45° (horizontal & vertical) 4. Isolated areas n.e. 1.00m2 shall be enumerated

DAMP PROOF MEMBRANE Example: WBLFF Damp Proofing And Tanking Coverings; 1 layer of Polythene sheet as specified, 1000 gauge or 0.25mm thick; laid on hardcore Over 300mm wide; flat; not exceeding 10° from horizontal; subsequently covered Over 300mm wide; sloping 10 - 45 degrees from horizontal; subsequently covered Over 300mm wide; vertical or sloping over 45 degrees from horizontal; subsequently covered Not exceeding 150mm wide; flat; not exceeding 10° from horizontal; subsequently covered Not exceeding 150mm wide; sloping 10 - 45 degrees from horizontal; subsequently covered Not exceeding 150mm wide; vertical or sloping over 45 degrees from horizontal; subsequently covered

DAMP PROOF MEMBRANE

DAMP PROOF COURSE 

G.28 – Generally 1. Description shall include: - Kind & quality of material - Gauge, Thickness or substances - Number of layers - Composition & mix of bedding material 2. No deduction shall be made for voids n.e. 0.50m2

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Example:

BRICKWORK Damp Proof Course Bituminous damp proof course as specified; 150mm laps; bedding in cement mortar (1:1); no allowance in measurement for laps

> 225mm wide shall be in m2

On horizontal surfaces

< 225mm wide shall be in m (stating the width)

On raking surfaces

No allowance in measurement shall be made for laps

On vertical surfaces

Horizontal, raking, vertical & curved work shall be

On curved surfaces

DAMP PROOF COURSE

BRICKWORK  

G.1.1 – Classification for heading a. Foundations b. Load bearing superstructure c. Non-load bearing superstructure

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G.3 – Generally 1. Description shall include: a. Kind, quality & size of bricks b. Type of bond c. Composition & mix of mortar  3. Separate classes given stating the thickness a. Walls

Example:

BRICKWORK Foundation 225mm thick Clay brick as specified; in cement and sand (1:3) mortar in English bond Walls/Retaining walls/Lift walls

TUTORIAL 2 WORK BELOW LOWEST FLOOR FINISH

TUTORIAL 2  –  WBLFF WORKS With reference to the following drawings and SMM2, take off the element WBLFF. 1.

Take off WBLFF works for Link House 20' X 70‘ Jenis A4 & A5

2.

Prepare the Bill of Quantity for the work 

Remarks: 

Excavate top soil for re-use in temporary spoil heaps 50m from site

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All disposal of excavated material shall be removed from site at contractor own source

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Filling of excavation arising – material arising from excavation

TAKING OFF LIST  –  TUTORIAL 2 

Excavation top soil

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Removal of excavated top soil

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Excavation in pit to receive pile cap

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Removal of excavated material

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Excavation in rock for pit excavation

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Excavation in trench to receive ground beam

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Removal of excavated material

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Excavation in rock for trench excavation

TUTORIAL 3 WORK BELOW LOWEST FLOOR FINISH

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With reference to the following drawings and SMM2, take off the element WBLFF.

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This is an individual assignment.

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Notes: •

Excavate topsoil 150mm deep to be used on site

•

Hardcore shall be cleaned broken stones or bricks

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Concrete to strip foundation shall be of Grade 20

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All bricks shall be well burnt ordinary clay bricks

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Damp proof membrane shall be 1000 gauge polythene

9000mm

    m     m      0      0      0      2      1

A

A 8000mm

    m     m      0      5      7      1

    m     m      0      0      3

50mm thk Grade 7 Lean Concrete

750mm