It is becoming critical to prove the environmental impacts of the building materials being used in construction. Trevor Richards, Operations Director for Cogent Consulting, explains the relevance of EPD’s to timber technology and offers guidance on how to produce them effectively.
With sustainability central to construction behaviour, Environmental Product Declarations (EPDs) play a crucial role in helping manufacturers and specifiers assess the impact of the products they choose. For timber technologies EPDs are especially important. They provide transparent, third party-verified data that support sustainability claims and influence specification in projects aiming for net zero or low-carbon outcomes.
EPDs – based on the EN 15804 standard – became mandatory in July 2022 for all new EPDs following a significant amendment (EN 15804+A2) approved in July 2019. This change requires EPDs to provide more detailed information on environmental impacts as well as aligning with the revised Construction Products Regulation (CPR). The revised CPR, which entered into force in January 2025, introduces additional requirements for EPDs that align with the EN 15804 standard.
What is an EPD and what do I do?
An EPD is a standardised document that communicates the environmental performance or impact of a product across its entire lifecycle. Developed in accordance with international standards, an EPD is grounded in a lifecycle assessment (LCA), which evaluates environmental impacts from raw material extraction through to end-of-life disposal.
An EPD is third-party verified to ensure the reliability and credibility of the information it presents. It allows for meaningful comparisons within the same product category and provides quantitative data on impacts such as carbon emissions, water consumption and energy demand. The structure of an EPD is modular, with environmental impacts reported by lifecycle stage, most commonly following the A1-A3 (cradle-to-gate) scope, and often including later stages (A4-C4) such as transport, use and disposal.
Why EPDs matter for timber technologies
Timber is often promoted as a low-carbon or even carbon-negative building material, but these claims require substantiation through credible, transparent data. For timber products, EPDs serve several key purposes. They provide transparent carbon accounting by quantifying carbon sequestration during tree growth alongside emissions released during processing, use and disposal. This enables fair comparison with competing materials such as steel and concrete by evidencing lower embodied carbon. EPDs also facilitate access to markets that require verified environmental data and enhance credibility with architects, contractors and clients pursuing sustainability targets.
Writing an EPD for Timber: Step-by-Step
Creating an EPD is a technically rigorous process, but one that firms like Cogent Consulting can support. The process includes four main stages: defining the product, conducting the LCA, compiling the declaration and undergoing independent verification.
The first step includes specifying the product type, timber species and source, intended use, declared unit of measurement and the geographic and temporal scope.
System boundaries must also be selected. These typically cover A1-A3 but and may extend to A4-A5, B, C and D. End-of-life scenarios are particularly significant for timber, and it is essential to clearly state whether the timber is likely to be incinerated, reused or recycled or disposed of totally.
The next step is the LCA and impact assessment. This data is modelled using LCA software such as SimaPro, GaBi or One Click LCA. For timber, carbon modelling is especially critical. The assessment must follow a Product Category Rule (PCR) tailored to timber construction products, usually aligned with EN 15804, to ensure consistency and comparability.
Once the LCA results are available, the information must be compiled into an EPD document. This includes a product description, functional unit, a summary of the manufacturing process, system boundaries, LCA results presented in tables, interpretation of those results and declarations on data quality and verification status.
To be recognised as a Type III environmental label, the EPD must undergo third-party verification by an approved body or programme operator such as BRE, IBU, or EPD International. The verifier assesses the EPD’s alignment with the PCR, the robustness of the LCA and the accuracy of the underlying data. Only after this verification can the EPD be formally published and registered.
Pitfalls to avoid
If in-house expertise is limited, engaging experienced LCA consultants is advisable, particularly given the complexities of timber modelling involving biogenic carbon and delayed emissions. Manufacturers should also plan for periodic updates as EPDs are generally valid for five years, but changes to processes or inputs may necessitate earlier revisions.
There are some pitfalls to avoid. Unclear or overly optimistic end-of-life scenarios can distort carbon calculations and assumptions should be explicit and conservative. Relying on generic data is another risk, as it can misrepresent actual environmental impacts. And overstating benefits without robust evidence can undermine the EPD’s credibility. Finally, using an incorrect or outdated PCR can result in the EPD being rejected.
Once the EPD has been verified, it should be made publicly accessible. This can be done via national databases and platforms such as Green Book Live or EPD International and NBS Source. Publishing the EPD on your company website also ensures wider visibility.
Why EPDs are a strategic investment for timber technology providers?
EPDs offer timber manufacturers a credible means of communicating environmental performance, allowing them to compete on measurable outcomes rather than unverified claims. EPDs also facilitate access to procurement frameworks that prioritise data-led decision-making. While the creation of an EPD can be a complex and resource-intensive endeavour, the benefits, in terms of reputation, market access and alignment with sustainable construction practices, are significant and enduring.
