Background of Quantity Surveying

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List of Figures List of Examples List of Tables Preface to the Irish Edition Acknowledgements

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General Introduction

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Historical background of quantity surveying; functions of bill of quantities; contract documentation; processes used in quantity surveying work; other measurement approaches; agreed rules of measurement; national standard building elements; other functions of the quantity surveyor; changes in quantity surveying techniques. 2

Measurement Procedures

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General rules; basic principles; tabulated rules; dimensions paper; measurement procedures; entering dimensions; spacing of items; waste; order of dimensions; timesing; deductions; measurement of irregular figures; alterations to dimensions; figured dimensions; numbering and titles of dimension sheets; order of taking-off; adjustment of openings and voids; descriptions; number of units; measurement of similar items; extra over items; deemed to be included items; accuracy in dimensions; drawn information; use of schedules; standard products; take-off lists; query sheets; preambles; provisional sums; prime cost sums; work in special conditions; composite items; worked examples. 3

Mensuration Applications

28

Introduction; girth of buildings; rectangular buildings; buildings of irregular outline; measurement of areas; irregular areas; trapezoids; segments; bellmouths, as at road junctions; measurement of earthworks; sloping site excavation; cuttings and embankments; measurement of pitched roofs; lengths of rafters; lengths of hips and valleys; roof coverings.

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Substructure

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Preliminary investigations; general items; site preparation; excavation to reduce levels; excavation of foundation trenches; disposal of excavated material; surface treatments; basement excavation; concrete foundations; concrete beds; precast concrete floors; other substructure work; brick and block walling; facework; damp-proof courses; damp-proof membranes; insulation; worked example; take-off list. 5

Brick, Block and Stone Walling

69

Measurement of brick and block walling; measurement generally; external walls; internal walls; chimney breasts and stacks; incidental works; damp-proof courses; rough and fair cutting; projections; special bricks/blocks; surface features; facework ornamental bands; facework quoins; composite walls; metal sheet cladding; rubble walling; natural stone; worked examples. 6

Fires, Flues and Vents

108

Chimney breasts and stacks; brickwork and blockwork in breasts and stacks; flues; fireplaces; flues to gas-fired appliances; vents; worked examples. 7

Floors and Partitions

116

Suspended floors; suspended concrete slabs; suspended timber floors; plates; floor joists; joist strutting; floorboarding; partitions; stud partitions; system partitions; worked examples. 8

Pitched and Flat Roofs

142

Introduction; pitched roofs; covering materials; interlocking tiles; slates, plain tiles, roof void ventilation; measurement of roof coverings; flashings; roof timbers; flat roofs; roof timbers; asphalt; built-up felt; sheet metal; rainwater goods; worked examples. 9

Internal Finishes

199

Sequence of measurement; wall finishes; floor finishes; skirtings and picture rails; ceiling finishes; painting and decorations; worked example. 10

Windows Order of measurement; windows; window schedules; worked examples.

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Doors

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Order of measurement; doors; door frames; worked examples. 12

Staircases and Fittings

272

Timber staircases; standard timber staircases; metal staircases; fittings; standard joinery fittings; worked example. 13

Water, Heating and Waste Services

285

Order of measurement; drawings for water supply and waste services installations; connection to water mains; pipework generally; water storage tanks or cisterns; holes for pipes; sanitary appliances; builder’s work in connection with services installations; schedules of water and waste services; heating and hot water installations; worked example. 14

Electrical Services

316

General approach to measurement; general rules; mains supply; transport installations; equipment; fittings; cables; conduit, trunking, cable trays and busbar trunking; final sub-circuits; sundries and builder’s work; worked example. 15

Drainage

328

Order of taking-off; drains; excavation of pipe trenches; disposal of water, beds and surrounds and vertical casings; drain pipes; pipe accessories; manholes/inspection chambers; sundries and associated works; sewage disposal plant; septic tanks; cesspits; soakways; worked example. 16

External Works

354

Roads, drives and paths; grassed areas; fencing and gates; trees, shrubs and hedges; worked example. 17

Bill Preparation and Production Presentation of a bill of quantities; structure of a bill of quantities; preliminaries; preambles clauses or specification; measured work; provisional, prime cost sums and contingencies; dayworks; collection and summaries; processes involved in the preparation of a bill of quantities; alternative formats of bills of quantities; computer applications; building software services; CATO enterprise; building information modelling; general conclusions.

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Appendix 1: List of Abbreviations Appendix 2: Mensuration Formulae Appendix 3: Metric Conversion Table Appendix 4: Specifications for Internal Finishes

393 394 396 399

Bibliography Index

402 405

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CHAPTER ONE

General Introduction HISTORICAL BACKGROUND OF QUANTITY SURVEYING The quantity surveying profession largely developed through the 20th century and in this century, but has now grown to such an extent that it forms the second largest sector or specialism in the membership of the Society of Chartered Surveyors (SCS) in Ireland and the Royal Institution of Chartered Surveyors (RICS) in the UK. Quantity surveyors are employed in private practices, public offices and by contractors, and they undertake a great diversity of work. In more recent times, quantity surveyors are engaged increasingly in the financial management of contracts, ensuring that clients secure value for money and that the completed projects provide substantial added value to the client’s property asset. In addition to being construction cost consultants, quantity surveyors are playing an increasingly important role today in project management, value management and facilities management. Furthermore, they are sometimes engaged as lead consultants for large projects, where they are responsible for the delivery of all professional services from inception to completion. The earliest mention of surveying as a profession in Ireland was in 1750. An Irish clergyman and architectural writer, John Payne, vicar of Castlerickard in County Meath, put his name to a “True Bill of Materials required for the Improvement at the Barrack of Horse at Trim” as “a full bill made by me John Payne, Clerk and Surveyor of Quantities”. The earliest quantity surveying firm of which records are available is a Reading firm in the UK which was operating in 1785. There is little doubt that other firms were in existence at this time and a number of Scottish quantity surveyors met in 1802 and produced the first method of measurement. Up to the middle of the nineteenth century it was the practice to measure and value the building work after it had been completed and bills of quantities were not prepared. The need for quantity surveyors became evident as building work increased in volume and building clients became dissatisfied with the method adopted for settling the cost of the work. In the seventeenth century the architects were responsible for the erection of buildings, as well as their design, and they employed a number of master craftsmen who performed the work in each trade. Drawings were of a very sketchy nature and much of the work was ordered during the course of the

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job. On completion each master craftsman submitted an account for the materials used and labour employed on the work. It later became the practice for many of the master craftsmen to engage ‘surveyors’ or ‘measurers’ to prepare these accounts. One of the major problems was to reconcile the amount of material listed on invoices with the quantity measured on completion of the work. Some of the craftsmen’s surveyors made extravagant claims for waste of material in executing the work on the site and the architects also engaged surveyors to contest these claims. General contractors became established during the period of the industrial revolution and they submitted inclusive estimates covering the work of all trades. Furthermore they engaged surveyors to prepare bills of quantities on which their estimates were based. As competitive tendering became more common the general contractors began to combine to appoint a single surveyor to prepare a bill of quantities, which all the contractors priced. In addition, the architect on behalf of the building owner usually appointed a second surveyor, who collaborated with the surveyor for the contractors in preparing the bill of quantities, which was used for tendering purposes. In later years it became the practice to employ one surveyor only who prepared an accurate bill of quantities and measured any variations that arose during the progress of the project. This was the origin of the independent and impartial quantity surveyor as he operates today. An excellent account of the development of quantity surveying in Ireland between 1860 and 1960 is provided by Aston (2007).

FUNCTIONS OF BILL OF QUANTITIES Frequently, one of the principal activities of the client’s quantity surveyor is the preparation of bills of quantities, although this surveyor would also perform a number of other functions. Consideration will now be given to the main purposes of a bill of quantities: (1) First and foremost it enables all contractors tendering for a contract to price on exactly the same information. (2) It limits the risk element borne by the contractor to the rates entered in the bill and thereby results in more realistic and competitive tenders. (3) It prompts the client and design team to finalise most project particulars before the bill is prepared, and ideally based on full production drawing and project specification. (4) After being priced it provides a satisfactory basis for the valuation of variations and adjustments to the final account. (5) Priced bills also provide a useful basis for the valuation of certified stage payments throughout a contract. (6) It gives an itemised list of the component parts of the building, with a full description and the quantity of each part, and could form an approximate

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checklist for the successful contractor in ordering materials and components and assessing his requirements of labour and other resources, and in programming the work. (7) After being priced, it provides a good basis for the preparation of cost analyses for use in the cost planning of future projects. (8) If prepared in annotated form, it will help in the locational identification of the work. With the increasing size and complexity of building operations, it would be a challenge for a contractor to price a medium to large-sized project without a bill of quantities. In the absence of a bill of quantities being prepared on behalf of the client, each contractor would have to prepare their own bill of quantities in the limited amount of time allowed for tendering. This places a heavy burden on each contractor and also involves additional costs which must be spread over the contracts in which they are successful. It could also result in higher cost to the client, as contractors may feel compelled to increase their prices to cover the increased risks emanating from this approach. Bills of quantities are not used to the same extent in non-traditional procurement arrangements like design and build. In design and build contractors normally price a brief provided by the employer which would usually include a schematic design and specification, which the contractor has to further develop into a scheme and fixed price.

CONTRACT DOCUMENTATION It will probably help the student at this stage to describe briefly the form of the contract documents on a traditional building contract incorporating a bill of quantities. The principal documents are as follows: (a) Conditions of Contract: The most common are the standard sets of conditions published by the Royal Institute of Architects in Ireland (RIAI). They define the terms under which the work is to be undertaken, the relationship between the client, architect and contractor, the duties of the architect and contractor, and terms of payment. These forms include the main RIAI form of contract (with or without quantities). The ‘with quantities’ form is that traditionally known as the yellow form in Ireland, where the bill of quantities forms part of the contract documentation. The ‘without quantities’ form is traditionally known as the blue form in Ireland, where the drawings and specification form part of the contract documentation and is the only basis on which the contractor prices the work. (b) Specification: This amplifies the information given in the contract drawings and bill of quantities, and describes in detail the work to be executed under

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the contract and the nature and quality of the materials, components and workmanship. Where there is a bill of quantities, the specification will not be a contract document unless so prescribed, and it may be incorporated in the bill of quantities in the form of preambles. (c) Bill of Quantities: This consists of a schedule of items of work to be carried out under the contract with quantities entered against each item, prepared in accordance with the Agreed Rules of Measurement, 4th Edition (ARM4). (d) Contract Drawings: These depict the details and scope of the works to be executed under the contract. They must be prepared in sufficient detail to enable the contractor to satisfactorily price the bill of quantities. (e) Form of Tender: This constitutes a formal offer to construct and complete the contract works in accordance with the various contract documents for the tender sum. Several alternative building procurement systems evolved in the 1980s and 1990s, giving greater choice and flexibility, and often resulting in faster completion and the transfer of greater risk to the contractor. These included design and build, management contracting, construction management, and design and manage. In more recent years the Irish government has introduced new Public Sector Building Contracts that shift significant risk onto the contractor. This creates, for the first time in Ireland, standard forms of building contract for a variety of public sector procurement arrangements (Howley and Lang, 2007).

PROCESSES USED IN QUANTITY SURVEYING WORK The traditional method of preparation of a bill of quantities can conveniently be broken down into two main processes: (1) ‘Taking-off’, in which the dimensions are scaled or read from drawings and entered in a recognised form on specially ruled paper, called ‘dimensions paper’, and (2) ‘Working-up’ which comprises squaring the dimensions, transferring the resultant lengths, areas and volumes into a convenient order for billing. The billing operation involves describing the work making up the complete project together with the quantities involved in a suitable order under Work Section or elemental headings. Developments in specialist software have eliminated much of the traditional ‘working-up’ process by allowing for the production of the bill of quantities directly following the input of the dimensions in the taking-off process. The most common approach used in Ireland is the ‘Direct Billing’ method where the quantity surveyor measures the net quantities of each item of work in the sequence it will be presented in the final bill of quantities.

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The term ‘quantities’ refers to the amounts of the different types of work fixed in position which collectively give the total requirements of the building contract. These quantities are set down in a standard form on ‘billing paper’, which has been suitably ruled in columns, so that each item of work may be conveniently detailed with a description of the work, the quantity involved and a suitable reference. The billing paper also contains columns in which a contractor tendering for a particular project enters the rates and prices for each item of work. These prices added together give the ‘Contract Sum’. It is the norm today that computer aided software is used in the preparation of bills of quantities, which ultimately print out the final quantities in a standard format. The recognised units of measurement are detailed in the Agreed ARM4. This document is extremely comprehensive and covers the majority of items of building work that are normally encountered. Many items are measured in metres and may be cubic, square or linear. Some items are enumerated and others, such as structural steelwork and steel reinforcing bars, are measured by the tonne. The bill of quantities thus sets down the various items of work in a logical sequence and recognised manner, so that they may be readily priced by contractors. A contractor will build up in detail a price for each item contained in the bill of quantities, allowing for the cost of the necessary labour, materials and plant, together with the probable wastage on materials and generally a percentage to cover establishment charges and profit. It is most important that each billed item should be so worded that there is no ambiguity as to the nature and extent of the item which is being priced. Contractors often tender in keen competition with one another and this calls for very skilful pricing to secure contracts. Where a bill of quantities is prepared in connection with a building contract, it will almost invariably form a contract document. The successful contractor is fully bound by the contents of all the contract documents when they sign the contract. The other contract documents on a normal building contract are the RIAI Articles of Agreement, Conditions of Contract, Contract Drawings and Form of Tender.

OTHER MEASUREMENT APPROACHES It would be misleading to imply that all measurement is based on the application of formalised rules of measurement. The use of ARM4 rules is mainly associated with traditional procurement systems where the architect is the lead consultant. This involves the preparation of the bills of quantities by the client’s quantity surveyor, and also in remeasurement for final account purposes. Other procurement methods, including specification and drawings, design and build, management contracting, etc., usually place the responsibility for preparing documentation, to facilitate pricing, upon the contractor or subcontractor. In these cases, measurement is still necessary as it forms the most

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frequently used mechanism for preparing a price. To achieve speed and reduce the cost of presentation in such circumstances, it is normal to concentrate the measurement on the cost significant items, which are also made inclusive of the associated peripheral aspects of the work. This practice departs from the notion of a standard method of measurement, as the cost significant items vary from project to project. However, the risk of misunderstandings arising are minimised by the measurer and estimator either being one and the same person or at least in close contact with one another. With the progressive adoption of various alternative forms of procurement, there has been a major shift in the point of measurement from the client’s quantity surveyor to contractors and subcontractors. The current RICS Measurement Initiative is proposing a suite of measurement rules for consistency and continuity throughout the entire cost and measurement process. The proposed documents will comprise rules and guidance notes covering the various stages of preparing cost estimates, bills of quantities and subsequently the whole life costs of construction. Although it has been established that a number of measurement approaches are employed within the construction industry, this does not alter the need to learn initially how to measure using the ARM4 rules. Once this technique has been mastered, it is a relatively straightforward matter to adapt to other forms of measurement.

AGREED RULES OF MEASUREMENT A working party was set up in 1991 by the SCS and the CIF to carry out research into the industries’ views of UK Standard Method of Measurement, 6th Edition (SMM6) and to investigate possible alternatives. The working party produced and examined pilot bills of quantities using a number of alternative methods of measurement in order to assess the differences. Eventually the quantity surveyors divisional committee of the SCS and the CIF agreed that the Principles of Measurement (International) (POMI) with amendments would come into operation from 1st April 1992 for a trial period of 18 months. The Department of Finance advised that their view was that SMM6 should continue to be used on all public sector contracts. The working party met regularly during the 18-month trial period. Both the SCS and the Construction Industry Federation (CIF) surveyed their members to establish their views on the operation of POMI. The CIF also received a report from a sub-committee of estimators setting out their views in relation to POMI. The working party decided to carry out a joint survey of the SCS and CIF members in June 1993. Thirty-four practices, twenty-six contractors and twelve subcontractors responded. Of those who responded 59% preferred POMI with amendments; 29% preferred SMM6 with amendments; 9% preferred SMM7; and 3% preferred other methods. Although 71% of quantity surveyors wanted a change, the working party

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met on 23rd August 1993 to consider the response to the survey and decide on further action. It was then that the recommendation was made that a new ARM should be drafted. In October 1993, the SCS and the CIF agreed to produce an agreed set of Rules of Measurement for use in Ireland. The ARM was designed in a tabular format and based on Work Sections similar to the Standard Method of Measurement, 7th edition (SMM7) in the UK. It was the objective that the ARM would be used on all major construction projects in both the public and private sectors. The ARM was designed to: (1) be an overall simplification of measurement, while still recognising cost significant items; (2) establish a closer link with present-day methods of construction; (3) introduce a tabular layout in work sections; (4) be a set of rules, which must be followed as distinct from principles of measurement; (5) rationalise the input required to produce a bill of quantities, preventing unnecessary measurement; (6) and create a more user-friendly document.

NATIONAL STANDARD BUILDING ELEMENTS Traditional trade bills of quantities are not compatible with the way the design of a building evolves. In designing, the architect is not thinking in terms of quantities of concrete or brickwork but in terms of elements of the building. A building element can be described as a functional unit of a building. The National Standard Building Elements (NSBE) committee in Ireland selected such design elements as the cost centres for cost control purposes. It is for this reason that the vast majority of quantity surveying practices present bills of quantities in an elemental format. Standard elements are common to the architect, engineer and quantity surveyor and therefore facilitate co-ordinated working between all the design team members. The following is a list of NSBE elements used by quantity surveyors in the production of costs estimates and bills of quantities in Ireland: (06) (19) (21) (22) (23) (24) (27) (28) (31) (32)

Preliminaries Substructure External Walls Internal Walls, Partitions Floors, Galleries Stairs, Ramps Roof Structure Frames External Walls: Completions within Openings Internal Walls: Completions within Openings

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(33) (34) (37) (41) (42) (43) (44) (45) (47) (5-) (6-) (7-) (10) (20) (30) (40) (50) (60) (70) (80)

Floors: Completions within Openings Stairs: Completion within Openings Roofs: Completions within Openings External Wall Finishes Internal Walls Finishes Floor Finishes Stair Finishes Ceiling Finishes Roof Finishes Services (Mainly Piped and Ducted) Services (Mainly Electrical) Fittings and Furniture Prepared Site Site Structures Site Enclosures Roads, Paths and Pavings Site Services (Mainly Piped and Ducted) Site Services (Mainly Electrical) Site Fittings Landscape, Play Areas

OTHER FUNCTIONS OF THE QUANTITY SURVEYOR The client’s quantity surveyor performs a variety of functions. The underlying theme of a quantity surveyor’s work is one of cost management rather than the preparation of bills of quantities and settlement of final accounts, whether they are engaged in private practice or in the public sector. The functions are: (1) Preparing approximate estimates of cost in the very early stages of the formulation of a building project, giving advice on alternative materials, components and types of construction and assisting with feasibility studies. (2) Cost planning and value analysis during the design stage of a project to ensure that the client obtains the best possible value for money, including adding value to property assets, preferably having regard to total costs using life cycle costing techniques. Costs should be distributed in the most realistic way throughout the various sections or elements of the building and tender figures should be kept within the client’s budget. (3) Advising on the most appropriate form of building procurement, having regard to the type of project, quality, speed of construction, apportionment of risk and price certainty. (4) Preparation of bills of quantities and other contract documents relating to the project.

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(5) Examining tenders and priced bills of quantities and reporting the findings. (6) Negotiating rates with contractors on negotiated contracts and dealing with cost reimbursement contracts, design and build, management and other forms of contract. (7) Valuing work in progress and making recommendations as to payments to be made to the contractor, including advising on the financial effect of variations. (8) Preparing the final account on completion of the contract works. (9) Advising on the financial and contractual aspects of contractors’ claims. (10) Giving cost advice and information at all stages of the contract and preparing cost analyses and cost reports to clients. (11) Specialist advice, such as technical auditing, valuations for fire insurance, giving advice on funding, grants, capital allowances and taxation, risk analysis and management, bank monitoring, project management, building services cost advice and other related matters including health and safety and quality control. The contractor’s quantity surveyor performs a different range of functions. In a contractor’s organisation, the senior quantity surveying function would typically be the responsibility of a senior chartered quantity surveyor who could have a senior executive or director status. The duties of the contractor’s quantity surveyor will vary according to the size of the company. These tend to be very wide in scope with the smaller companies, but rather more specialised with the larger firms. In the smaller company, their activities will be of a general nature and include: (1) Preparing bills of quantities for small contracts and agreeing measurements with the client’s quantity surveyor. (2) Collecting information about the cost of various operations from which the contractor can prepare future estimates. (3) Preparing precise details of the materials required for the projects in hand and compiling target figures so that the operatives can be awarded production bonuses. (4) Preparing interim costings so that the financial position of the project can be ascertained as the work proceeds and appropriate action taken where necessary; planning contracts and preparing progress charts in conjunction with the general foremen/site manager and making application to the architect for variation orders if drawings or site instructions vary the work. (5) Agreeing subcontractors’ accounts; placing subcontract orders and comparing the costs of alternative methods of carrying out various operations, so that the most economical procedure can be adopted. (6) Advising on the implementation of contract conditions and different contractual methods.

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In larger companies, the contractor’s quantity surveyor will not usually cover such a wide range of activities, since different departments handle specific activities. During the training period, the trainee quantity surveyor will probably spend some time in each department. One particular function, which is very complementary to the functions of the quantity surveyor, is that of the estimator. The estimator is vital to the success of the contracting organisation. The estimator’s main responsibility is to accurately predict the most economic costs for construction, in a way which is both clear and consistent. Estimators also manage the production of the estimate and must ensure that there are adequate resources for this task. They must also co-ordinate other company departments, such as programming, buying and construction, to their work requirements, producing information on time and in the correct format. The estimator is also responsible for liaising with general management on construction methods and available resources. Estimators must fully understand measurement codes and how this affects the build-up of rates used for estimating purposes. For example, they must be aware that all wastage of materials must be taken into account when they are pricing tenders. In addition, estimators are frequently required to prepare tenders based on drawings and specifications. This means that they will have to measure the quantities for that tender. They must also be constantly in tune with the situation both on-site and off-site. They must continually analyse and revise to achieve success in tender competitions.

CHANGES IN QUANTITY SURVEYING TECHNIQUES The quantity surveyor acts as an essential advisor on matters of cost, between clients, designers, engineers and building contractors. In addition to preparing bills of quantities, they can find employment opportunities in the professional disciplines of quantity surveying with advice on a consultancy basis about development finance, construction cost and life cycle operating costs for construction costs. The future direction of quantity surveying will be influenced by industralisation, structural transformation of economies, information technology breakthroughs and increased globalisation of construction markets. The roles of quantity surveyors have evolved along with these changes and challenges. In 1998 the RICS QS Think Tank Report noted that clients were critical of traditional quantity surveying services and were demanding a different and more comprehensive range of services. In Ireland there are considerable variations of quantity surveying firms, in respect to ownership, structure, size and total workforce. In relatively recent years we have seen established UK practices taking controlling interests in the larger quantity surveying practices in Ireland. Although current practices in Ireland are dominated by traditional practices, there is considerable evidence that practices have diversified from the more traditional boundaries.

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This book is focused on the production of bills of quantities, which remains a very important core service provided by professional quantity surveying practices. There is substantial usage of specialist software by quantity surveying firms in the production of bills of quantities which will be discussed in greater detail in Chapter 17.

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CHAPTER FOUR

Substructure PRELIMINARY INVESTIGATIONS Before taking off any dimensions the quantity surveyor normally makes a careful study of all the drawings relating to the project to obtain the overall picture and become familiar with the main details. At the same time it is necessary to ensure that all the drawings are complete and that there are adequate specification particulars, to enable the measurement to proceed unhindered by inadequate information. The next step is usually a visit to the site to obtain details and measurements of any work required on the site, often termed ‘prepared site’. These works include breaking up paving, taking down boundary walls and fences, and possibly demolishing existing buildings, felling trees, grubbing up hedges, and similar work. Some contracts involve alterations to existing buildings and these are sometimes termed ‘spot items’ and are normally kept together in a separate ARM Work Section of the bill of quantities headed ‘Demolition and alterations’ (ARM4: Work Section C). Many of the details relating to spot items will also need to be obtained on the site. When visiting the site the quantity surveyor should also be on the look-out for any unusual items which affect cost, and which should accordingly be included in the billed descriptions. A check on the type of soil and groundwater level comes into this category, unless the information is supplied by the engineer, probably in the form of particulars from trial pits or boreholes excavated on the site. With landfill or brownfield sites, it is also necessary to check on possible land contamination, with the likely consequential high cost of removing contaminated soil and remedial measures, including the extraction of landfill gases such as methane.

GENERAL ITEMS It is necessary to give details of ground investigation reports indicating the nature of the ground, ground water table level and date when established (PreContract level), trial pits or boreholes stating their location, over or under ground services, nature of contaminated or hazardous materials, location drawings, material filling requirements and limitations on methods of execution.

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SITE PREPARATION Removal of trees and tree stumps is measured as an enumerated item, including grubbing up roots, disposal of materials and filling voids, classified in the girth ranges (D22.1.2.1.1). Tree girths are measured at a height of 1.00 m above ground and stump girths at the top of the stumps, as per D23, Measurement Rules, Item 1. Clearing site vegetation is measured in m2 with a description sufficient for identification purposes (D22.1.4.0.0). Site vegetation embraces bushes, scrub, undergrowth, hedges, trees and tree stumps ≤ 0.45 girth, as per D23, Measurement Scope, Item 2. The first building operation is normally the excavation of the topsoil for preservation over the whole area of the building and this usually forms the first excavation item in the Excavating and Earthwork Work Section of the bill of quantities. The area is measured to the outer extremities of the foundations in m2 and the average depth, often 150 mm, is included in the description (D22.3.6.3.0). Disposal of topsoil on the site in temporary spoil heaps for reuse is covered by a separate cubic item stating the location of any spoil heaps (D24.3.9.13.2). Spreading hardcore on the site to make up levels is measured in m3, distinguishing between average thicknesses ≤ and > 225 mm (D24.4.12.16.4). Disposal of excavated material off the site is measured in m3, giving details where appropriate of specified locations (D24.3.10.15.3) or handling and where active, toxic or hazardous materials are involved (D24.3.10.15.3). If the existing topsoil over the site of the building is to be preserved, then this forms a separate billed item measured in m2, stating the method of preserving the turf, such as stacking in rolls in a specific location (D22.2.5.2.0).

EXCAVATION TO REDUCE LEVELS Where the site is sloping or the ground levels are generally higher than is required then further excavation is required to reduce the level of the ground to the specified formation level. This excavation is measured in m3, as excavation to reduce levels (D22.3.7.4.0), giving the appropriate maximum depth range. The excavation rules in ARM4 are based on all excavation being carried out by mechanical plant.

EXCAVATION OF FOUNDATION TRENCHES Foundation trench excavation is measured in m3, stating the commencing level where >250 mm below existing ground level, as per D23, Measurement Rules, Item 4 and the maximum depth range in accordance with D22.3.9.4.0, namely ≤ 2.00 m and > 2.00 m depth in 2 m stages.

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Quantities for all excavation items shall be taken as the bulk before excavation, as per D23, Measurement Rules, Item 3. Excavating below groundwater level is given in m3 as extra over any types of excavating (D22.4.12.0.0). Excavating around existing services is measured in m as extra on items for excavating, stating the type of service, such as gas or water mains, electricity or ESB cables or sewers (D22.4.13.5.0). While excavating around existing services crossing excavation is an enumerated extra over item (D22.4.13.6.0), since it is likely to entail hand digging, and most other excavation will be carried out by machine. Breaking out rock; concrete; reinforced concrete; brickwork, blockwork or stonework shall each be described and measured separately in m3 as extra on items of excavating (D24.1.1.1–4.0), while breaking out existing hard pavings is measured in m2, stating the thickness, as extra on excavating (D24.1.1.6.0). Rock is defined as any material which is of such size or position that it can only be removed by wedges, special plant or explosives, as per D25, Measurement Scope, Item 1. Obstructions are typically included in the bill of quantities as a provisional quantity, as the exact extent of such work will be unknown at the time of preparing the tender documentation. This work will be later remeasured, as and when encountered on-site and the extent of work will be recorded and agreed between the contractor and the client’s quantity surveyor and paid at the rates included in the priced bill of quantities. Working space allowance to excavations, categorised in five types of excavation as D24.2.3–7, is measured in m2, where the face of the excavation is < 0.60 m from the face of formwork, rendering, tanking or protective walls, as per D25, Measurement Rules, Items 4–8. Working space tends to apply to more complex foundations, such as basements. Three sets of levels will be required before foundation work can be measured: (1) bottom of foundations, (2) ground levels and (3) finished floor levels. When measuring foundation trenches it is advisable to separate the trenches into external and internal walls. Where the external wall foundation is of constant width and the site is level, its measurement presents no real difficulty with the length being obtained by the normal girthing method, as outlined in Chapter 3. Where the site is sloping and stepped foundations are introduced the process of measurement of the foundation trench excavation is more complex, since each length of trench will have to be dealt with separately. After measuring the excavation for external wall foundations, the internal wall foundations will be taken, and this will often involve a number of varying lengths and widths of foundations, which are best collected together in waste and the drawing suitably marked up as each length is extracted. Care must be taken to adjust for the overlap of trenches at the intersection of the external and internal walls as shown in Figure 13. The external wall foundation trench will have been measured around the whole building in the first instance, and the hatched section will have to be

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Seeley and Winfield’s Building Quantities Explained

600

100 internal walls Extent of overlap

Spread of foundations

900

300 cavity wall

Figure 13

Intersection of internal and external walls.

deducted at each intersection when arriving at the length of internal foundation trench.

DISPOSAL OF EXCAVATED MATERIAL The subsequent disposal of excavated material forms a separate billed item in m3, either of soil to be stored on-site (D24.3.10.14–15.3), used as filling to make up levels (D24.4.12.16.4), filling to excavations (D24.4.11.16.4), or to be removed off the site (D24.3.10.15.4), as illustrated in Figure 14 for a traditional strip foundation. In the first instance, the total volume of excavation to reduce levels, foundation trenches etc. should be added together, which is followed with a deduction for material that may be required to be retained for backfilling to excavations.

Filling to excavations, topsoil

Taken as backfilling with previously excavated material Taken as disposal of excavated material off-site

Figure 14

Excavate topsoil for preservation and disposal on-site

Backfilling with imorted hardcore Excavate trench

Excavating and filling: traditional strip foundation.

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However, in other circumstances different approaches are more appropriate, such as for the trench fill foundation as shown in Figure 15 and the alternative strip foundation in Figure 16. In both cases the best approach is to take the volume of trench excavation as disposal of excavated material off-site. Handling of excavated material is normally at the discretion of the contractor unless detailed in the description (D24.3.10.15.3).

SURFACE TREATMENTS Compacting the bottom of the excavation is a deemed to be included item and is covered in the excavation item as per D23, Deemed to be Included, Item 6. Surface treatments, such as blinding hardcore with sand, is measured in square metres (D24.5.13.0.0). Compacting of filling is deemed to be included also, as per D25, Deemed to be Included, Item 5. Excavate topsoil for preservation and disposal on-site Filling to excavations, topsoil

Excavate trench and disposal of excavated material off-site

Figure 15

Excavating and filling: trench fill foundation.

Filling to excavations, topsoil

Taken as backfilling with previously excavated material

Figure 16

Excavate topsoil for preservation and disposal on-site

Backfilling with imported hardcore Excavate trench and disposal of excavated material off-site

Excavating and filling: strip foundation with hardcore backfill internally.

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BASEMENT EXCAVATION Basement excavation is measured to the outside of foundations in m3 stating the maximum depth range. Working space allowance is measured in m2 where formwork, rendering, tanking or protective walls are required to the face of construction below starting level of excavation but only where the face of the excavation is ≥ 0.60 m distant, as per D25, Measurement Rules, Item 4. The area measured is calculated by multiplying the girth of the tanking or protective walls by the depth of excavation below the starting level of the excavation, where the height of the formwork or protective walls below starting level of excavation is > 1.00 m or where the bottom of the formwork or protective walls is > 1.00 m below starting level of excavation, as per D25, Measurement Rules, Item 5. Working space shall be measured full depth where rendering or tanking is required, as per D25, Measurement Rules, Item 6. Additional earthwork support, disposal, backfilling, work below groundwater level and breaking out are deemed to be included (D25, Deemed to be Included, Item 1). Earthwork support is a deemed to be included, as per D23, Deemed to be Included, Item 4.

CONCRETE FOUNDATIONS Concrete particulars are to include the kind and quality of materials, mix details, tests of materials and finished work, methods of compaction and curing and other requirements (F36: Information Required), but much of this information may be included in preamble clauses or cross-references to project specification clauses. Concrete poured on or against earth or unblinded hardcore shall be so described (F36.4.0.0.2). Concrete foundations include attached column bases and attached pile caps, as per F37, Measurement Scope, Item 1, while isolated foundations include isolated column bases and pile caps as per F37, Measurement Scope, Item 2. Beds and slabs include attached beams and beam casings, as per F37, Measurement Scope, Item 4. In-situ concrete is measured in m3 and the degree of difficulty in placing the concrete is reflected by giving the thickness ranges ≤ 150 mm and > 150 mm in the case of beds and slabs (F36.9–10.1.0.1). On a sloping site the concrete foundations will probably be stepped and it will be necessary to measure the additional concrete at the step and a linear item of formwork to the face of the step classified in two stages of depth: ≤ 250 mm and 250–500 mm (F42.2.1.0.0). Where the formwork exceeds 500 mm in height this is measured in m2 (F42.2.2.0.0). In the example shown in Figure 17 it will be necessary to add a 450 mm length of foundation 225 mm thick.

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Concrete foundation 21 N/mm2 (20 mm2 aggregate)

225

225

450

Figure 17

Stepped foundation.

Note: Concrete has been classified by strength, i.e. 21 N/mm2 (20 mm aggregate), as an alternative to a designed mix to BS5328 or a specified mix of concrete, such as 1:3:6 – 20 mm aggregate) If the concrete foundations are reinforced with fabric reinforcement, the reinforcement is measured net in m2 stating the mesh reference, weight per m2 and minimum laps (F40.2.4.3). Bar reinforcement is billed in tonnes, keeping each diameter (nominal size) separate, although it will be entered by length on the dimensions sheet, distinguishing between straight, bent and curved bars (F40.1.1.1.0). Hooks and tying wire, and spacers and chairs which are at the discretion of the contractor are deemed to be included (F41, Deemed to be Included, Items 1–2). Figure 18 shows an attached ground beam to an in-situ concrete bed. Beds and slabs include attached beams and beams casings, as per F37, Measurement Scope, Item 4. A typical take-off entry for this item is then shown. 150 concrete bed

150

1000 Attached ground beam 500

Figure 18

Attached ground beam.

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CONCRETE WORK: In-situ Concrete 30 N/mm2 (20 mm aggregate) Beds ≤ 150 mm; reinforced (F36.9.1.0.1) 10.00 10.00 0.15 15.00 (main slab) –––––

20 m3

10.00 0.50 1.00 5.00 (attached ground beam) ––––– ––––– 20.00 ––––– –––––

CONCRETE BEDS In-situ concrete beds are measured in m3, stating the appropriate thickness range as ≤ 150 mm or > 150 mm and including in the description where poured on or against earth or unblinded hardcore. Treating the surface of in-situ concrete is classified and given in m2 (F38.2.6–13.0.2–5). Common surface treatments include power floating, trowelling, hacking, grinding, sand blasting, bush hammering and brushed. A tamped finish is deemed to be included, as per F39, Deemed to be Included, Item 5. Hardcore and similar beds are measured in m3, classified as to whether the average thickness is ≤ or > 250 mm, the nature of the filling material and its source and/or treatment (D24.4.12.16.4). The measurement of filling is illustrated in Example 1. Where the surface of hardcore filling requires blinding, this is measured separately in m2 (D24.5.13.0.0).

PRECAST CONCRETE FLOORS Precast concrete beam and block floors are now being used increasingly, particularly for the ground floors of domestic buildings, as they provide a soundly constructed floor, free from dry rot and other forms of insect and fungal attack to which timber floors are susceptible, with a good platform to receive the insulation and floor finish. A typical form of construction is illustrated in Figure 19. Such work is measured in m2 in accordance with F46.2.1.1. The concrete, reinforcement and formwork to be included in composite construction shall be described, as per F47, Measurement Rules, Item 2. Another alternative to reinforced in-situ concrete slabs on upper floors, as shown in Example 11, is to use

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precast concrete hollow core slabs grouted after laying. These are measured in the same way as the precast concrete beam and block floor in Example 2. This type of floor has the advantage of faster erection times and the virtual elimination of shuttering and pouring of concrete.

Figure 19

Precast concrete block and beam floor.

OTHER SUBSTRUCTURE WORK It has been customary to include all substructure work in a separate section of the bill, including brickwork up to and including damp-proof course. However, ARM4 subdivides this work into several Work Sections: D: Excavating and Earthwork; F: Concrete Work; and G: Brickwork and Blockwork. Hence the substructure work will be subdivided into these Work Sections in the bill of quantities, albeit within an overall elemental bill called Substructure. The substructure element will include for measuring all the work, including the

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rising walls up to the damp-proof course level, which is typically 150 mm above the external ground level of the building.

Brick and Block Walling Block and brick walling is measured in m2 and described as wall in trenches, stating the nominal thickness, such as 100 mm, and whether there is facework (fair finish) on one or both sides (G48.2.1.0). It should be noted that all brickwork is deemed to be measured on its centreline, as per G49, Measurement Rules, Item 1. The formation of the cavity is measured in m2 (G52.1.1.1.1). Wall ties shall be given in the description stating the type and spacing, as per G53, Measurement Rules, Item 1.

Facework Brick facework is included in the measurement of the brickwork on which it occurs, with a description of the kind, quality and size of bricks, type of bond, composition and mix of mortar and type of pointing (G48: Information Required). In practice these particulars could alternatively be included in preamble clauses or be cross-referenced to a project specification. Specifying the precise type of brick or block is a better approach as it simplifies the task of the estimator in determining its relative hardness and ease of laying, and should lead to more realistic pricing.

Damp-proof Courses Damp-proof courses are measured in m where it is ≤ 225 mm wide (G52.3.5.2.3) and in m2 where > 225 mm wide (G52.3.6.2.3). Vertical, raking, horizontal and stepped work, are so described (G52.3.5.2.3–7). The description of the damp-proof course contains particulars of the materials used, including the kind and quality of the materials (G52: Information Required). No allowance is made for laps, as per G53, Deemed to be Included, Item 1.

Damp-proof Membranes Damp-proof membranes are measured under ARM4 Work Section I: Roofing, Cladding and Waterproofing. Radon membranes are also measured under this section. This work is normally measured as one continuous sheet in m2 stating that it is horizontal and > 300 mm in width (I66.2.1.1).

Insulation Floor insulation falls are measured under ARM4 Work Section J: Woodwork: Ironmongery, Accessories and Sundries. This work is measured in m2 stating the specification and thickness (J84.5.14.5.0).

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WORKED EXAMPLE A Worked example follows covering the substructure to a small building. The importance of a logical sequence in taking off cannot be overemphasised. It simplifies the taking-off process and reduces the risk of omission of items. On the drawings a decimal in the dimensions indicates measurements in m, for example 10.000. Where there is no decimal marker, the dimensions are normally in millimetres.

Take-off List It is good practice to prepare a take-off list prior to commencing the take off. This ensures that items are measured in the corrrect sequence, as they would appear in the final bill of quanities. The exercise also helps in consulting ARM4 to see if there are any unusual classifications of work. Most importantly, the list will help to raise any appropriate queries with the project architect or engineer in respect of discrepencies in project information or omitted information.

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TAKE-OFF LIST DRG REF:

Drawings 1 and 1a Drawing 2 (Alternative Precast Block and Beam detail)

ARM ref

Description

Unit

EXCAVATION AND EARTHWORKS: Excavation m2

D22.3.6.3.0

Excavation topsoil for preservation; average depth 150 mm

D22.3.7.4.0

Excavation to reduced levels; depth ≤ 2 m

m3

D22.3.9.4.0

Excavation foundation trenches; depth ≤ 2 m

m3

D24.1.1.1.0

Provisional; extra over on excavation items for breaking up rock

m3

D24.3.8.10.0

Disposal of water; surface

Item

D24.3.9.13.2

Disposal; topsoil for preservation; location; weed killer

m3

D24.3.10.15.0 Disposal of excavated material off-site

m3

D24.4.11.16.0 Filling clause 804; to excavation; average thickness > 250 mm

m3

D24.4.12.16.0 Filling clause 804; to make up levels depth ≤ 250 mm thick

m3

D24.5.13.0.0

m2

Surface treatments; sand blinding to hardcore

CONCRETEWORK: In-situ Concrete F36.4.0.0.2

Foundations; poured on or against earth

m3

F36.9.1.0.0

Concrete beds; ≤ 150 mm thick

m3

F36.20.4.2.0

Sundries; concrete filling to cavity

m3

F38.2.6.0.0

Power floating slab

m2

CONCRETEWORK: Reinforcement F40.1.1.1.0

Reinforcement – Bars

Tns

F40.2.4.3.0

Mesh; A142; lapped 300 mm

m2

BRICKWORK AND BLOCKWORK: Brickwork / Blockwork G48.2.1.0.0

Blockwork; walls in trenches 100 mm thick

m2

G48.7.3.0.0

Labour on blockwork

Item

BRICKWORK AND BLOCKWORK – Ancillaries G52.1.1.1.1 G52.3.5.2.3

Forming cavities; between new walls; 100 mm wide; 150 mm deep cavity insulation

m2

DPC; ≤ 225 mm; 100 mm laps; horizontal

m

WATERPROOFING: Waterproof and Gas Proof Non-Metal Flexible Sheet Coverings I66.2.1.1.0

DPM; horizontal > 300 mm wide

m2

WOODWORK: Ironmongery, Accessories and Sundries J84.5.14.5.0

Insulation; horizontal; > 300 mm wide

m2

J84.5.14.5.0

Insulation; vertical; 150 mm high

m2

ALTERNATIVE PRECAST CONCRETE FLOOR CONCRETE WORK: Sundries F38.2.6.0.0

Surface finish; power floating

m2

CONCRETE WORK: Precast Concrete F46.4.1.2.0

Composite construction; precast beam and block floor slab

m2

BRICKWORK and BLOCKWORK – Ancillaries to Brickwork G52.9.14.4.0

Wall ventilators

Nr

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150 mm SLAB

GL 10.000

150

Seeley and Winfield’s Building Quantities Explained

600 1050

175 h/c

300

56

300

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Index Accuracy of Dimensions 22 Adjustment of Openings 20 Agreed Rules of Measurement 6–7, 12 Deemed to be Included 14, 22 General Attendances 26 General Rules 12–13 Measurement Rules 14 Measurement Scope 14 Special Attendances 26 Tabulated Rules 13 Asphalt 152 Attendances 26 Back Drop Manhole 334 Back Inlet Gully 333 Bellmouths 34 Benching 335 Bill of Quantities 4, 12, 374–92 Alternative Formats 381 Computer Applications 382 Contingencies 375, 379 Dayworks 375, 378 Functions 2–3 Measured Work 375, 378 Preambles 375, 378 Preliminaries 375, 377 Presentation 374 Prime Cost Sum 379 Production 380–1 Provisional Sums 379 Structure 375 Blockwork 50, 69 Brick, Block and Stone Walling 69–107 Attached Piers 72 Brick and Block Walling 69–74 Chimney Breasts and Stacks 71 Composite Walls 74 Facework Ornamental Bands 73 Facework Quoins 73 Projections 71

Rough and Fair Cutting 71 Rubble Walling 76 Special Bricks and Blocks 70 Surface Features 72 Worked Example 77–107 Builder’s Work in Connection 287 Building Information Modelling 390–2 Ceiling Finishes 204–5 Cesspits 337 Channels 335 Chimney Breasts and Stacks 108 Cisterns 287 Cold Water Supply 285 Builder’s Work in Connection 287 Connection to Water Mains 286 Holes for Pipes 287 Pipework 286 Water Storage Tanks 287 Worked Example 292–315 Composite Items 27 Composite Walls 74 Computer Applications 382–90 Building Information Modelling 390–2 Building Software Services 383–8 Cato Enterprises 388–90 Concrete Suspended Floors 116 Construction Industry Federation (CIF) 6 Contingencies 379 Contract Documentation 3–4 Bills of Quantities 4 Conditions of Contract 3 Contract Drawings 4 Form of tender 4 Specification 3 Contractor’s Quantity Surveyor 9 Cost Planning 8 Damp Proof Courses

50

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Index

Damp Proof Membrane 50 Dayworks 379 Deemed to be Included 13, 22 Design and Build 4 Design Schedules 23 Dimensions Paper 14 Alterations to Dimensions 17 Deductions 16 Description Column 15 Descriptions 20 Dimension Column 15 Figured Dimensions 18 Measurement of Irregular Figures 17 Numbering of Dimension Sheets 18 Order of Dimensions 15 Signposting 15 Spacing of Items 15 Squaring Column 15 Timesing Column 15 Title of Dimension Sheets 18 Waste 15 Direct Billing 4 Doors 253–71 Door Frames 254 Worked Examples 255–71 Drainage 328 Drain Pipes 332 Pipe Accessories 332 Worked Example 339 Drawings 22 Drives 354 Earthworks 34–8 Cuttings and Embankments 36–8 Sloping Site Excavation 34–6 Electrical Services 316–27 Builder’s Work in Connection 317 Busbar Trunking 317 Cable Trays 317 Cables 317 Conduit 317 Final Sub-circuits 317 Fittings 317 Mains Supply 317 Sundries 317 Transport Installation 317 Trunking 317 Worked Example 320 Estimator 10 External Walls 69 Worked Examples 77–86 External Works 354–73

Drives 354 Fencing 355 Gates 355 Grassed Areas 355 Hedges 356 Paths 354 Roads 354 Scrubs 356 Trees 356 Worked Example 356–73 Extra Over Items 24, 32 Facework 50 Fencing 355 Fire, Flue and Vents 108 Breasts and Stacks 108 Chimney Breasts and Stacks 108 Fireplaces 108 Flues 108 Flues to Gas-fired Appliances 108 Vents 108 Worked Example 111–15 Fireplaces 109 Fittings 275–6 Kitchen Fittings 276 Flashings 149 Flat Roofs 152 Worked Example 190–8 Floorboarding 118 Floor Finishes 202–3 Floors 116–18 Suspended Concrete Slabs 116 Suspended Timber Floors 116–18 Worked Example 122–33 Flues to Gas-fired Appliances 109 Form of Tender 4 Gable Ladders 150 Gates 355 General Attendances 26 Girth of Buildings 28–31 Rectangular Buildings 28 Irregular Buildings 30 Grassed Areas 355 Gullies 333 Heating and Hot Water Installation 288–91 Insulation 50 Inspection Chambers 335 Internal Finishes 199–236 Ceiling Finishes 204

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Index

Floor Finishes 202 Painting and Decorating 205–6 Skirtings and Picture Rails 203 Wall Finishes 200 Worked Example 208–36 Internal Walls 71 Internal Block Walls 87 Worked Example 87–9 Management Contracting 4 Manholes 333 Covers 334 Benchings 335 Step Irons 335 Measurement of Areas 31–4 Bellmouths 34 Irregular Areas 32 Segments 33 Trapazoids 32 Mensuration Applications 28–40 Metal Casement Windows 104 Worked Example 104–7 Metal Sheet Cladding 75 Metal Staircases 273–5 Mortar Mixes 70 National Standard Building Elements 7–8 Natural Stone 76 Nominated Subcontractors 26 Nominated Suppliers 25 Painting and Decorating 205–7 Partitions 119–21 Stud Partitions 120 System Partitions 120–1 Worked Example 134–41 Paths 354 Pipework 286 Pitched Roofs 39–40, 142–89 Covering Materials 142 Flashings 149 Hips 151 Interlocking Tiles 142 Plain Tiles 147 Roof Timbers 149 Roof Void Ventilation 147 Slates 142 Worked Examples 156–89 Preambles 24, 378 Preliminaries 375–7 Prepared Site 41 Prime Cost Sums 379

Principles of Measurement (International) (POMI) 6 Provisional Sums 379 Public Sector Building Contracts

4

Quantity Surveyor 1 History 1–2 Work Processes 4–5 Functions 9–10 Changes 10–11 Query Sheets 24 Roads 354 Rodding Eye 336 Roof Coverings 142–8 Interlocking Tiles 142 Plain Tiles 147 Slates 142 Roof Ventilation 147–8 Royal Iristitution of Chartered Surveyors (RICS) 1 Rubble Walling 76 Worked Example 98–103 Septic Tanks 336–7 Shrubs 356 Skirtings and Picture Rails 203 Slate Coverings 142, 146 Soakaways 338 Society of Chartered Surveyors (SCS) 1 Special Attendances 26 Specifications 3, 378 Staircases 272–5 Metal 273–5 Timber 272–5 Worked Example 278–84 Standard Method of Measurement, 7th Edition 6 Standard Products 23 Step Irons 335 Stud Partitions 120 Substructure 41–51 Basement Excavation 46 Concrete Beds 48 Concrete Foundations 46 Disposal of Excavated Material 44 Excavation of Foundation Trenches 42 Excavation to Reduce Levels 42 General Items 41 Precast Concrete Floors 48 Preliminary Investigations 41

407

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408

Index

Site Preparation 42 Spot Items 41 Surface Treatment 45 Worked Example 52–68 Suspended Concrete Floors 116 Suspended Timber Floors 116–17 System Partitions 120 Taking-off 4 Order of Taking-off Take-off Lists 23

19

Timber Floors Trees 356 Vents

116–17

109

Wall Finishes 200–2 Waste Services 285 Window Schedules 238–9 Windows 237–52 Worked Examples 239–52 Working-up 4