Whole life carbon assessment scope under the RICS standard

A whole life carbon assessment prepared to the RICS standard covers every life cycle module in BS EN 15978, from raw material supply through to end of life, reported in kilograms of carbon dioxide equivalent per square metre of gross internal area. The scope question that decides whether your assessment is accepted is not which modules exist. It is which ones you have reported, whether you have reported them separately, and whether the reference study period and floor area basis match the benchmark you are comparing against.

Get those four things aligned and the assessment is straightforward. Get them wrong and the reviewer cannot tell whether your building is better or worse than the comparator, which usually ends in a request to redo the work.

The modules and the three headline figures

The life cycle stages come from BS EN 15978 and are used across the industry:

Three aggregate figures matter in planning. Upfront carbon is A1 to A5, the emissions committed before anyone occupies the building. Embodied carbon adds B1 to B5 and C1 to C4. Whole life carbon takes everything, including operational energy at B6 and water at B7.

Module D is reported separately and never netted off the total. That rule exists because module D is a projection about future markets rather than an emission avoided today, and a report that folds it into the headline number reads as an attempt to flatter the result.

What the RICS standard fixed in its second edition

The second edition of the RICS whole life carbon assessment standard replaced the earlier professional statement and applies to assessments from mid 2024 onwards. Three changes affect scope directly.

A5 was broken down so that pre-construction demolition and site works, construction waste and construction site activities are reported as separate components rather than as a single lump. That matters on brownfield sites, where demolition can carry more carbon than the new substructure.

The treatment of sequestration and biogenic carbon was tightened, with reporting requirements that stop timber schemes claiming a large negative number without the corresponding end of life release.

And the standard set clearer expectations on data quality, with environmental product declarations prepared to EN 15804 preferred over generic database figures for the elements that dominate the total.

Name the edition you have used in the report. Reviewers compare against benchmarks that are edition-specific.

Reference study period and floor area basis

The default reference study period for buildings under the standard is 60 years. If your scheme uses a different period, and there are legitimate reasons on some building types, state it prominently and adjust any benchmark comparison accordingly. A 60 year assessment and a 100 year assessment are not comparable at the B modules.

Floor area is the other silent error. The standard reports against gross internal area. Benchmarks published on a gross external area basis, or on a net internal area basis, will make the same building look better or worse for no physical reason at all. State the area, state the basis, and show the calculation.

Where a whole life carbon assessment is actually required

There is no national requirement in England for a whole life carbon assessment on every application. The requirement comes from two places.

In London, the London Plan requires whole life-cycle carbon assessments for referable applications, using the Greater London Authority's template and guidance, with an assessment at planning stage and a further one after construction. The template is prescriptive about modules and format, so use it rather than a bespoke spreadsheet.

Outside London, the requirement comes from adopted local plan policy or from a validation checklist. A growing number of authorities ask for one on major schemes, and some ask for a simpler carbon statement instead. Check the adopted policy and the local list before scoping the work, because the two documents are different exercises.

Proposals to introduce a national embodied carbon regulation have been discussed for several years without being made law. Treat anything of that sort as not in force until it is.

Scoping the assessment on a real project

Start with what is being demolished. On a site with existing buildings, the retention option has to be tested, because the carbon case for demolition is the first thing a reviewer looks for. A Pre-redevelopment Audit that records what exists, what could be reused in situ and what could be recovered gives the assessment its baseline.

Then set the elemental scope: substructure, superstructure, internal finishes, fittings, building services, and external works within the site boundary. Services are frequently underestimated because the design is undeveloped at planning stage, and a placeholder allowance drawn from an industry dataset should be labelled as such rather than presented as a calculated figure.

Then the data. Use environmental product declarations for concrete, steel, glazing, insulation and cladding, which between them usually account for most of the upfront total. Generic data is acceptable for minor elements. Record the source for every material in an appendix, because the appendix is what a reviewer checks when the headline looks optimistic.

Illustrative example. A six storey residential block submits an upfront carbon figure that sits comfortably under the benchmark. The reviewer finds A5 reported as a single lump, module D netted off the total, and the area given as gross external. Correcting all three moves the number above the benchmark without changing a single design decision. This example is illustrative only.

How it fits with the other sustainability documents

Whole life carbon overlaps with three other submissions, and duplicating content between them causes contradictions that reviewers pick up.

The Energy Statement deals with operational regulated energy, the energy hierarchy and the carbon reduction against the Building Regulations target. That is module B6 territory, and the whole life assessment should take its operational figures from the energy modelling rather than generating its own.

The Circular Economy Statement covers design for disassembly, material reuse and waste targets, which drive the C and D modules. Where the circular economy statement claims a reuse rate, the carbon model should reflect it.

The Sustainability Statement pulls the policy compliance narrative together. Keep the numbers in one place and cross-refer, rather than restating them three times with three different rounding conventions.

Timing, and the one thing that changes the outcome

Run the first assessment at concept design, when the structural grid, frame material and substructure are still open. By the time the scheme is being drawn for submission, the decisions that move the number most have already been made, and the assessment becomes a reporting exercise rather than a design tool.

There is an honest limitation worth stating. Whole life carbon numbers carry real uncertainty, particularly at the B and C modules where you are forecasting 60 years of replacement cycles and waste treatment. Precision to three decimal places in a spreadsheet does not make the forecast accurate. Report ranges where the standard allows it, and be candid about the assumptions.

Councils usually expect a suitably qualified author for carbon assessment work, and professional review is strongly advised. A Whole Life Carbon Assessment drafted by PlanScope is structured to the standard's module reporting and flags the inputs that have to be confirmed by that specialist.

This is general guidance, not legal advice. Check the adopted policy and validation requirements with your local planning authority before scoping the work.

See PlanScope pricing if you want to draft the sustainability document set before commissioning the specialist modelling.

PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.