Pricing Documents & Bills Of Quantities

Section 1

Purpose

The Bill of Quantities (BQ) is the primary pricing document for traditionally procured building contracts. Prepared by the QS in accordance with NRM 2: Detailed Measurement for Building Works (2nd edition, effective 1 December 2021), it provides tenderers with a complete, consistent schedule of measured quantities, enabling contractors to price the works on an equal basis without independently measuring the drawings. The BQ also forms part of the contract and, post-contract, governs the valuation of variations, interim payments and the final account.

NRM 2 defines the structure, content and measurement rules for all building work sections — from demolitions (Section 3) through to builder's work in connection with M&E (Section 41). The BQ must be structured to reflect the contract programme and trade sequence, enabling the QS to extract activity-level valuations for interim certificates and to identify the cost impact of variations by work section.

For Design and Build contracts, the pricing document is typically a Contract Sum Analysis (CSA) rather than a BQ — see GN-TD-10. For NEC4 contracts, work is priced via an Activity Schedule (Option A/C) or a Bill of Quantities (Option B/D). The choice of pricing document must align with the selected contract form and be confirmed before tender documents are compiled.

Section 2

Key Principles

NRM 2: Detailed Measurement for Building Works (2nd edition, effective 1 December 2021): mandatory RICS measurement rules for BQ preparation; defines BQ types, composition, work sections, provisional and PC sums, codification, and ICMS mapping.
NRM 2 Work Sections 3–41: cover all building work trades from Demolitions (S3) to Builder's Work in Connection with M&E Services (S41) — each section has specific measurement rules, item descriptions and coverage rules.
Defined and undefined provisional sums (NRM 2): a defined provisional sum has sufficient design information to price nature, construction method, fixity and quantity; an undefined provisional sum does not — tenderers cannot include programme allowances for undefined sums.
Prime cost (PC) sums (NRM 2): supply-only rates for materials or goods of unknown precise quality; excludes fixing costs, contractor OHP — tenderers add these separately. PC sums should be minimised at Stage 4.
RICS E-Tendering (2nd edition, 2010): RICS recommends web-based tender extranets for BQ distribution, particularly for projects over £3m; disk/CD acceptable; email not recommended as primary distribution method.
JCT Standard Building Contract with Quantities (SBC/Q 2016): the BQ forms a contract document; quantities are at the employer's risk — errors in measured quantities are valued under the contract variations machinery.

Section 3

Practical Application

Step 1

Confirm the BQ structure and format with the client before taking-off commences. Agree: work section sequence (NRM 2 sections 3–41); elemental or trade format; codification system (if required for BIM or post-contract cost reporting); and whether a paper or electronic BQ will be issued.

Step 2

Gather all technical design information: architectural drawings at 1:50/1:20, structural engineer's drawings and schedules, M&E specification and layout drawings, landscape drawings, specialist subcontractor specifications. Confirm the information is complete and co-ordinated before measurement begins.

Step 3

Take off measured quantities for each NRM 2 work section. Record dimensions in a taking-off sheet or digital measurement software. Apply NRM 2 measurement rules strictly — particularly coverage rules that define what is included in each measured item.

Step 4

Draft item descriptions for each measured item using NRM 2 description conventions: work category, material/product, execution method, finished size/thickness, location, and any preamble cross-references. Clear, unambiguous descriptions reduce the risk of post-contract disputes about what was included.

Step 5

Insert provisional sums for work not fully designed. Classify each as defined or undefined per NRM 2 rules. Insert PC sums for specified-by-others supply items (e.g. client-selected tiles, ironmongery, loose furniture). Keep these to a minimum — extensive provisional sums indicate incomplete design.

Step 6

Structure the BQ preliminaries section using NRM 2 Section 1 format: fixed charges, time-related charges, and method-related charges. The preliminaries section should mirror the form sent to tenderers for pricing and align with the contract's preliminaries schedule.

Step 7

Prepare the BQ summary, collection pages and cover page. Apply final checks: arithmetic check on all collections; confirm all provisional and PC sums are listed in the summary; confirm the BQ total reconciles with the Pre-Tender Estimate.

Step 8

Issue the BQ to tenderers as part of the tender documents. Use NRM 2's recommended codification system if BIM integration or elemental cost reporting is required. Retain the unpriced BQ as the authoritative measurement record for post-contract use.

Section 4

Common Mistakes to Avoid

Using undefined provisional sums for work that should be measured — extensive undefined sums transfer risk back to the client, undermine cost certainty, and prevent tenderers from building in reasonable programme allowances.
Using PC sums for work that should be specified and measured at Stage 4 — PC sums are appropriate only where the client genuinely has not selected the product; using them to avoid specification decisions is poor practice.
Omitting coverage rules from the preambles section — without clear coverage rules, tenderers make different assumptions about what is included in measured items, making tender analysis and post-contract valuation difficult.
Not reconciling the BQ total to the Pre-Tender Estimate before issue — a material discrepancy between the two should be investigated and resolved before tenders go out, not after they are returned.
Issuing a BQ in a format that does not support post-contract cost management — the BQ structure should enable easy interim valuation, variation pricing and final account preparation, not just tendering.

Section 5

APC Competency & Quick Reference

APC Competencies: Procurement & Tendering (L2) | Cost Management (L2) | Design Economics & Cost Planning (L2) | Commercial Management (L1)

What are the three types of Bill of Quantities defined in NRM 2?

NRM 2 defines: (1) Firm BQ — quantities are accurate and complete; forms a contract document; employer bears risk of quantity errors; (2) Approximate BQ — quantities are estimated; used where design is not fully complete; (3) Schedules of rates — no quantities; tenderers price rates only; used for term contracts or frameworks where the scope is unknown.

What is the difference between a defined and undefined provisional sum?

NRM 2 defines a provisional sum as defined when sufficient information exists to describe: (i) the nature and construction of the work; (ii) how and where it is fixed; (iii) a quantity indicator; and (iv) any limitations. An undefined provisional sum lacks this information. Tenderers must include programme allowances for defined sums but cannot do so for undefined sums — this affects programme planning and risk pricing.

What is a Prime Cost (PC) sum and when is it appropriate?

A PC sum is a supply-only allowance for materials or goods where the client has not yet selected a precise product (e.g. tiles, sanitary ware, ironmongery). The PC sum excludes fixing, contractor OHP, and ancillary items — the tenderer prices these separately. At Stage 4, PC sums should be minimised; their use should be confined to genuine client-specified supply items, not to avoid specification decisions.

Section 6

Pricing Documents & BQ Checklist

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BQ structure and format agreed (NRM 2 work sections; codification; electronic format)

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Full technical design information received and confirmed as coordinated

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Quantities taken off for all NRM 2 work sections (3–41)

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Item descriptions prepared per NRM 2 description conventions

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Provisional sums classified (defined / undefined) and minimised

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PC sums used only for genuine client-specified supply items

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Preliminaries section structured per NRM 2 Section 1 (fixed / time-related / method-related)

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Arithmetic check on all BQ collections and summary

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BQ total reconciled to Pre-Tender Estimate before issue

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BQ issued to tenderers via secure e-tendering portal

Section 7

CPD Learning Outcomes

Prepare a Bill of Quantities in accordance with NRM 2: Detailed Measurement for Building Works (2nd edition, 2021), applying the correct measurement rules, description conventions and coverage rules for each work section.
Distinguish between firm BQs, approximate BQs and schedules of rates, and between defined and undefined provisional sums and PC sums, and select the appropriate document type for each project context.
Explain how BQ structure directly affects post-contract cost management — interim payment assessment, variation valuation and final account preparation — and design the BQ accordingly.

Section 8