NRM2 Explained: What UK Builders and Developers Need to Know About the New Rules of Measurement

According to Designing Buildings Wiki, NRM2 formally replaced the Standard Method of Measurement, seventh edition, known as SMM7, which had been the industry standard since 1988. NRM2 became operative on 1 January 2013 and formally superseded SMM7 on 1 July 2013.

The differences between NRM2 and SMM7 go beyond a name change. NRM2 uses a more comprehensive, element-based structure and work breakdown structures rather than SMM7’s trade-based approach, provides clearer rules for quantifying contractor-designed work and risk, and measures more items separately rather than treating them as “deemed included” within another item. NRM2 also gives more detailed guidance on preliminaries, including how overheads and profit should be dealt with, and on the actual content, structure, and format of a bill of quantities itself, which SMM7 addressed less thoroughly.

It’s worth noting that SMM7 hasn’t disappeared entirely. Some older or ongoing contracts still specifically reference SMM7, and where a contract names SMM7 as the applicable method, that’s what should be used, rather than substituting NRM2 rules simply because they’re more current.

NRM2 organises building work into a structured set of work sections, running from preliminaries through to external works, each covering a distinct category of construction activity. These sections give a bill of quantities a consistent, recognisable structure across different construction projects, so a contractor’s estimating team can move between jobs without relearning how the document is organised each time.

NRM2 also sets out clearer rules for provisional sums, allowances included in a bill of quantities for work that can’t yet be fully defined or detailed when the document is prepared. Compared with SMM7, NRM2 gives more defined categories for provisional sums, which reduces ambiguity over what a provisional sum actually covers and how it should be treated once the work is eventually defined and priced.

NRM2 applies to building works specifically. Civil engineering projects, such as roads, bridges, and major infrastructure, are generally measured under a separate standard, CESMM4, the Civil Engineering Standard Method of Measurement, published by the Institution of Civil Engineers rather than RICS.

Where a project includes both building work and a genuinely civil engineering element, such as a building with associated infrastructure, it’s worth being clear about which parts fall under NRM2 and which fall under CESMM4, rather than applying one standard across the whole project simply because it’s more familiar.

A typical project moves from an early cost plan, prepared under NRM1 with limited design information, through to a detailed bill of quantities prepared under NRM2 once drawings are sufficiently developed. Understanding this progression matters because it explains why an early cost estimate and a later, NRM2-based bill of quantities can show different figures for the same project, they’re prepared at different stages, with different levels of design information available.

A typical project moves from an early cost plan, prepared under NRM1 with limited design information, through to a detailed bill of quantities prepared under NRM2 once drawings are sufficiently developed. Understanding this progression matters because it explains why an early cost estimate and a later, NRM2-based bill of quantities can show different figures for the same project, they’re prepared at different stages, with different levels of design information available.

NRM2’s consistent structure also supports cost value reconciliation during a project, the ongoing process of comparing actual costs incurred against the values allowed for in the original bill of quantities. Because NRM2 measures and codes work consistently across different buildings and projects, it produces reliable cost data that’s more straightforward to track and reconcile, rather than trying to compare figures measured under inconsistent or unclear rules.

Builders and developers who aren’t quantity surveyors themselves still benefit from understanding what NRM2 is. A bill of quantities prepared properly under NRM2 gives you a document you can genuinely compare between contractors, since every tenderer is pricing the same defined scope rather than their own interpretation of it. It also gives you a clearer basis for agreeing variations during the build, since work not originally covered can be measured and priced using the same consistent rules as the rest of the document.

For anyone commissioning building works, from a straightforward extension to a full development scheme, asking whether quantities have been measured to NRM2 is a reasonable question to put to your estimator or quantity surveyor.

Getting NRM2 measurement right depends on having sufficiently developed drawings and specification information before detailed measurement begins, since NRM2’s rules assume a certain level of design maturity. Projects measured too early, before the design is settled, risk a bill of quantities that needs significant revision once details change, undermining the consistency NRM2 is meant to provide in the first place.