EPD Explained

What is an EPD?

An Environmental Product Declaration (EPD) is a standardised document that reports the environmental impact of a construction product across its lifecycle. Think of it as a nutrition label for building materials - it provides verified data on carbon emissions, energy use, water consumption, and waste generation.

EPDs are produced following international standards (EN 15804 in Europe, ISO 14025 globally, and ISO 21930 for buildings and civil engineering works) and verified by independent third-party bodies. This standardisation is what makes them useful - you can compare products on a like-for-like basis, provided you understand the declared units and lifecycle boundaries.

The rules that make EPDs within a product family directly comparable are called Product Category Rules (PCRs). PCRs sit underneath the higher-level standards and define exactly which methods, scenarios, and indicators apply to a given product type. Two EPDs written under the same PCR can be compared directly. Two EPDs written under different PCRs - even for similar products - usually cannot.

Why EPDs matter for material selection

As embodied carbon becomes a regulatory and client requirement, EPDs provide the evidence base for material decisions. Without product-specific data, specifiers rely on generic industry averages that can be significantly different from actual product performance.

EPDs also help distinguish genuine sustainability performance from marketing claims. A manufacturer stating their product is 'low carbon' means little without verified data to back it up. An EPD provides that verification.

Tip. When comparing materials on Matera, look for the verified EPD badge. This indicates the embodied carbon data shown is backed by a third-party verified declaration, not a generic estimate.

Types of EPDs you will encounter

Not every document calling itself an EPD carries the same weight. Knowing which type you are looking at tells you how much to trust it and what it can be used for.

Topic	Detail
Third-party verified EPDs	the gold standard. Produced under ISO 14025 and EN 15804, externally verified, published by a recognised programme operator, and valid for five years. Accepted for green building certifications and procurement.
Variant EPDs	derived from a parent third-party verified EPD where the products share materials, processes, and function. Useful for product families (e.g. one EPD covering several thicknesses or colours). Still ISO 14025 compliant.
Project EPDs	internally verified, not publicly registered, prepared for a specific contract or tender. Look for wording like 'internally verified'. Acceptable for the project they were written for, but not equivalent to a published EPD for general use.
System-verified EPDs	auto-generated in bulk by software where the generation system itself is verified, rather than each individual document. Convenient for manufacturers with large catalogues, but offers less per-product scrutiny than a fully verified document.
Self-declared environmental claims (ISO 14021, Type II)	manufacturer statements with no third-party verification. They must be truthful and substantiated, but they are not EPDs and should not be compared directly to verified EPD figures.

Watch out. If a supplier sends you a 'carbon datasheet' or 'environmental statement' rather than a registered EPD with a programme operator and registration number, it is almost certainly a self-declared claim - useful context, but not equivalent evidence.

Key things to check in an EPD

EPDs contain a lot of data. Focus on these critical elements first.

1.Declared unit

What quantity does the data refer to? Compare products using the same unit (e.g. per m², per kg, per m³).

2.Lifecycle stages covered

Check which stages are included (A1-A3 is common). An EPD covering only A1-A3 is not comparable to one covering A1-C4.

3.GWP (Global Warming Potential)

The headline carbon number, measured in kg CO₂e. Lower is better, but only compare like-for-like units and scopes.

4.Validity date

EPDs expire - typically after 5 years. They should also be re-issued earlier if the manufacturer changes raw materials, suppliers, or processes in ways that affect the figures.

5.Programme operator and verifier

Look for recognised programme operators (e.g. EPD International, BRE, IBU) and independent third-party verification.

6.Type of EPD

Third-party verified, variant, project, or system-verified - each carries different weight. Self-declared 'environmental statements' are not EPDs.

How to use EPDs in practice

EPDs are most valuable when used comparatively. Here is a practical framework for incorporating them into material selection.

Topic	Detail
Compare like-for-like	ensure declared units, lifecycle boundaries, and functional performance are equivalent before comparing GWP figures
Combine with other criteria	carbon data should inform decisions alongside cost, performance, lead time, and buildability
Request EPDs early	ask suppliers for EPD availability during initial engagement, not after specification is complete
Use for reporting	EPD data feeds directly into whole-building lifecycle assessments (WBLCA) required by frameworks like BREEAM and LEED

Common pitfalls

These are the most frequent mistakes when working with EPDs. Being aware of them helps you avoid misleading conclusions.

Comparing products with different declared units (e.g., per kg vs per m² at different thicknesses)
Comparing A1–A3 figures from one product with A1–C4 figures from another
Treating Module D credits as guaranteed - they depend on actual end-of-life scenarios
Ignoring the reference service life - a product lasting 30 years has different lifecycle impact than one lasting 60
Over-relying on a single metric (GWP) while ignoring other impact categories like acidification or resource depletion

Watch out. An EPD reports environmental data - it does not make a value judgement about whether a product is 'sustainable'. That assessment depends on context, application, and comparison with alternatives.

How Matera uses EPD data

On Matera, materials with verified EPDs display embodied carbon data directly on their product cards and detail pages. This allows you to compare products based on actual, verified performance rather than assumptions.

Suppliers can upload EPD documentation to their profiles, and Matera indicates whether carbon data is EPD-backed or estimated from category benchmarks. Look for the verified badge when browsing materials.