BREEAM backs new industry guidance on project-level embodied carbon comparisons

The embodied carbon community in North America has a new tool in its arsenal. The Embodied Carbon Harmonization & Optimization (ECHO) Project, a coalition of leading built environment organizations including the USGBC, the Carbon Leadership Forum, CAGBC, ASLA and BRE, has published Project LCA Baseline Guidance: ECHO Aligned Guidance for Adoption, a pilot document that provides aligned guidance on conducting fair comparative project lifecycle assessments (LCAs) so embodied carbon programs and policies can easily adopt a consistent approach to baseline modelling practices.

BRE is proud to stand behind this publication as an ECHO member, and BREEAM sees it as a valuable step toward the kind of methodological consistency the industry needs.
 

Why baselines matter

Anyone who has tried to substantiate an embodied carbon reduction claim knows the problem this resource is looking to solve. A reduction is only meaningful if it is measured against a credible, fair point of comparison. Two project teams claiming a ‘20% reduction’ can mean very different things if one team’s baseline was generous and the other’s was rigorous. Without shared rules for how that baseline is constructed, comparisons across projects, programs and certifications lose their integrity.

The new ECHO guidance tackles this directly. It does not attempt to define embodied carbon budgets or set intensity benchmarks. Instead, it focuses on something more foundational: how to build a baseline that is functionally equivalent to the proposed design, so any difference in embodied carbon reflects a genuine design decision. It covers consistent methodology, functional equivalency for buildings, infrastructure and sites, acceptable strategies for claiming reductions, default assumptions for baseline assemblies and materials, and best practices for documentation.
 

How this connects to BREEAM

This is territory BREEAM knows well. Fair, well-documented comparison is at the heart of how BREEAM’s Materials category evaluates embodied carbon and life cycle impact, and the principles in this new ECHO guidance align with the approach BREEAM already takes: consistent tools and datasets between baseline and proposed models, clearly defined functional equivalence and transparent documentation of any deviation from default assumptions.

That said, this is not yet a like-for-like swap. For projects in the U.S. and Canada, BREEAM certification still relies on its own embodied carbon benchmarks, set out in Mat 01 of BREEAM International New Construction V7, and ECHO baselines have not been approved as an alternative basis for comparison within BREEAM’s manuals. BRE is watching closely how this guidance develops and will consider its role in future BREEAM releases.

Second, it reflects something BRE has long believed: that embodied carbon assessment only becomes trustworthy at scale when the industry comes together on shared definitions rather than each program inventing its own. BREEAM does not work in isolation and has always drawn on the best available external guidance, standards and data sources — this publication is a strong addition to that landscape.
 

BREEAM’s role in advancing practices in North America

BRE’s involvement in the ECHO Project reflects its continued leadership in advancing rigorous, consistent approaches to embodied carbon across North America. As BREEAM continues to expand its presence in the region, that leadership includes working alongside leading North American organizations to shape the standards and practices that will guide the industry’s approach to embodied carbon and building performance. This is part of BREEAM’s broader commitment to supporting the evolution of sustainable building practice across the region — not simply adapting an established methodology to a new market but actively contributing to the standards and conversations shaping its future.

Supporting the ECHO Project LCA Baseline Guidance is one example of that ongoing engagement. While ECHO baselines are not yet incorporated into BREEAM’s own manuals or benchmarking approach, BRE’s participation allows BREEAM to contribute its expertise while continuing to learn from and respond to the unique needs of the North American market.
 

What project teams should do next

The guidance has been released as a beta pilot. Project teams evaluating comparative LCAs, whether for BREEAM certification or another purpose, can review the document and consider how its baseline development approaches and default assumptions relate to their own methodology. ECHO will continue collecting feedback through June 2027 ahead of a revised final version.
 

Looking ahead

Embodied carbon assessment is maturing quickly, and guidance like this is part of what allows that maturity to translate into real, comparable reductions rather than a patchwork of claims that cannot be verified against one another. BRE’s continued involvement in efforts like ECHO reflects a broader commitment: to make sure that wherever BREEAM operates, its methodology is built in step with, not apart from, the standards the local industry is converging on.

For more information, see the Project LCA Baseline Guidance on the ECHO Project website.