One year after AECOM’s research: what’s changed for whole life carbon assessment?

One year on from AECOM’s landmark research into embodied carbon in buildings, whole life carbon assessment continues to gain momentum across the built environment. BCIS executive director James Fiske explores what has changed over the past 12 months and what the latest developments could mean for future regulation.

One year has passed since the Ministry of Housing, Communities and Local Government published AECOM’s research into embodied carbon in buildings. The report marked an important milestone, reflecting growing government recognition of the role whole life carbon assessment and reporting can play in supporting the UK’s net zero ambitions.

Over the past 12 months, the government has continued to take a measured approach to regulation. While it has not committed to mandatory whole life carbon assessments or embodied carbon limits for new buildings, it has continued the conversation, largely through its Carbon Budget and Growth Delivery Plan and the Future Homes and Buildings Standards.

At the same time, the industry has become even more fervent in its pursuit to reduce emissions, with new standards, frameworks and guidance emerging. Together, these developments suggest the technical foundations that could support future regulation are becoming more established.

September 2025: BREEAM New Construction Version 7 strengthens whole life carbon assessment

One of the first major developments following AECOM’s report was the launch of BREEAM New Construction Version 7 (NC V7).

The latest version of the sustainability assessment framework places greater emphasis on whole life carbon, including benchmarking and reporting for both operational and embodied carbon.

It also strengthens alignment with wider sustainability reporting requirements, including the EU Zero Energy Buildings definition and optional EU Taxonomy criteria.

More than simply updating a certification scheme, the update reflects a broader shift towards treating whole life carbon assessment as an established element of building performance, rather than an optional exercise.

March 2026: UK Net Zero Carbon Buildings Standard lands

One of the most significant developments of the past year was the publication of Version 1 of the UK Net Zero Carbon Buildings Standard.

For the first time, the UK has an industry-backed definition of a net zero carbon aligned building.

Formed through collaboration across the built environment sector, the standard applies to numerous work categories, including new build, retrofit and extension projects, across 13 sectors. It sets measurable performance targets and reporting requirements that projects must meet to demonstrate alignment with the standard.

The publication also provides greater consistency in an area where approaches have often differed, giving clients, designers and contractors a shared criteria for assessing what zero carbon means in practice. As of July, formal verification of net zero carbon aligned buildings has been possible.

March 2026: NISTA handbook reinforces whole life carbon management

March also saw the publication of the National Infrastructure and Service Transformation Authority’s whole life carbon management handbook.

The handbook brings together existing government policy and established industry guidance, including PAS 2080 principles, into a practical resource for project delivery.

It builds on the Transforming Infrastructure Performance 2030 Roadmap and encourages project teams to apply best practice whole life carbon management throughout a project’s life cycle.

This includes applying the PAS 2080:2023 emissions hierarchy to identify opportunities to reduce emissions, considering carbon impacts at a system level and collaborating across projects to share knowledge and data. It’s welcome guidance and should support the growing integration of whole life carbon management into mainstream project delivery.

March 2026: Future Homes and Buildings Standards set regulatory precedent

The introduction of the Future Homes and Buildings Standards in March 2026 marked another step towards improving the operational performance of new homes and buildings.

Although the standards focus primarily on operational energy performance rather than embodied carbon, they reinforce the wider direction towards lower-carbon construction and higher-performing buildings. Critically, it proved the government is willing to use regulation as a tool for reducing emissions in the built environment.

For the industry, the standards also serve as a reminder that operational and embodied carbon cannot be considered in isolation if genuinely low-carbon buildings are to be delivered.

March 2026: UKGBC progress report highlights the scale of the challenge

The UK Green Building Council’s (UKGBC) Whole Life Carbon Roadmap Progress Report provided one of the clearest assessments of progress over the past year.

The report reiterated that built environment emissions needed to fall by 24% between 2018 and 2024 to remain on track with the pathway set out in UKGBC’s 2019 Roadmap. Instead, reported emissions fell by 14% over the same period.

Operational emissions fell by 21%, close to the Roadmap’s target. Reported embodied carbon emissions, however, increased by 5%, compared with the 20% reduction identified in the Roadmap. The report concluded that total emissions would need to reduce around three times faster to recover lost ground by 2027.

The report also noted that embodied carbon remains a significant policy gap. It underlined that while embodied carbon is responsible for up to half of new buildings’ life cycle emissions, it is not currently regulated. UKGBC argued that mandatory whole life carbon assessments and, in time, embodied carbon limits could help support progress towards national carbon targets.

Other recommendations included requiring whole life carbon assessments for major developments, supporting retrofit through policy and investment, accelerating grid decarbonisation and embedding climate outcomes throughout planning, design and delivery.

April 2026: RICS launches CLEAR to improve consistency

In April, the Royal Institution of Chartered Surveyors (RICS) launched the Coalition for Life Cycle Emissions Alignment and Reporting (CLEAR).

Developed in partnership with the World Business Council for Sustainable Development and the Global Building Data Initiative, the three-year programme aims to improve alignment between different whole life carbon methodologies used internationally.

Rather than replacing existing standards, CLEAR seeks to understand where methodologies differ and develop a more consistent framework for reporting and assessment.

As whole life carbon reporting becomes more widely adopted globally, initiatives such as CLEAR may help improve consistency and transparency across different markets.

May 2026: UKGBC publishes a new Whole Life Carbon Framework

UKGBC built on this momentum with the publication of its updated Whole Life Carbon Framework.

Where the 2019 framework focused on defining net zero carbon buildings, the new version places greater emphasis on implementation. It sets out principles and practical actions for reducing whole life carbon and managing residual emissions throughout a building’s life cycle.

The framework is structured around four objectives:

• minimise embodied carbon
• optimise operational energy and water performance
• manage residual carbon emissions
• optimise user outcomes

It is intended for organisations involved throughout the building life cycle, including local authorities, developers, designers, manufacturers and facilities managers.

July 2026: embodied carbon reaches the House of Commons

The House of Commons debate on embodied carbon in buildings in July provided further insight into the government’s current position.

During the debate, MPs discussed the emissions associated with construction materials, opportunities to reuse existing buildings and the role of design and materials choices in reducing emissions.

Responding to the debate, Samantha Dixon, Parliamentary Under-Secretary of State for Housing, Communities and Local Government, referred to AECOM’s research and acknowledged the work taking place across the industry to improve embodied carbon measurement and reporting.

She also said the government recognised the potential benefits of more consistent assessment through better data and greater transparency.

However, Dixon explained the government remains cautious about introducing regulation before methodologies become more consistent. She noted that whole life carbon assessments rely on a range of assumptions, including design choices, building lifespan, data quality, construction methods and end-of-life scenarios. Greater consistency, she suggested, would be needed before mandatory reporting could be considered.

The debate offered a clearer indication of the government’s intentions. Rather than questioning the value of whole life carbon assessment, ministers indicated that future regulation is likely to depend on further improvements in consistency and evidence.

The bigger picture

Looking across the past year, the overall direction is clear.

The government has made quieter progress, taking a cautious approach to stricter carbon regulation as it considers the implications of introducing new requirements.

At the same time, the industry has made significant strides, developing the standards, frameworks and guidance needed to support more consistent whole life carbon assessment.

Taken together, these developments mean the foundations for any future regulatory approach are much stronger than they were 12 months ago.

It’s now the built environment sector’s task to continue making the case for proportionate, evidence-led regulation. Maintaining dialogue with the government and keeping whole life carbon assessment high on the agenda will be paramount if the built environment is to make meaningful progress in reducing emissions.

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