From LCA to EPD —
how it is verified and published

If you already have an LCA study, or you have just received an EPD request from a client, a retailer or a contracting authority, this guide explains exactly what happens between “I have an LCA report” and “I have a public, verified document in a registry”.

For the conceptual difference between LCA, EPD and CFP, see the comparative guide LCA vs EPD vs CFP — this article goes deep on the LCA → EPD route, step by step.

Why you cannot jump straight to “I want an EPD”

The most common misunderstanding among new clients is the belief that an EPD can be ordered directly, like a certificate. In reality, an EPD is the public, verified form of an LCA study — it cannot exist without one. The actual order of work is:

• 01

  The LCA study

  An LCA study compliant with ISO 14040/14044 is carried out — or taken over, if one already exists.

• 02

  Adaptation to the PCR

  The study is adapted to the Product Category Rule (PCR) relevant to the product in question.

• 03

  Independent verification

  An accredited third-party verifier independently validates the calculation and the documentation, in accordance with ISO 14025.

• 04

  Publication

  The declaration is published in an international registry and becomes a public document, with a standard validity of five years.

Skip step 3 and you do not have an EPD — you have an internal LCA, however rigorous the calculation may be.

Step 1 — the LCA study as the foundation

An EPD is built on a complete LCA, covering all 19 environmental impact indicators (not only GHG emissions) and at minimum modules A1–A3 (cradle-to-gate). For construction, EN 15804+A2 additionally requires modules C1–C4 (end of life) and module D (benefits beyond the life cycle) — these became mandatory with the transition from +A1 to +A2, completed in October 2022.

The point where most time is lost is not the calculation but the collection of primary data from the manufacturer and its suppliers: energy consumption on the production line, raw material recipes, transport. Secondary data (from recognised databases such as Ecoinvent) fills the gaps, but a credible EPD relies on as much primary, plant-specific data as possible rather than on industry averages.

Step 2 — the Product Category Rule (PCR)

A generic LCA cannot become an EPD without being mapped onto the Product Category Rules (PCR) specific to the material. These standardise the assumptions, the functional unit and the system boundaries, so that EPDs within the same category are comparable across different manufacturers. Each programme operator (EPD International, IBU, EPD Norge) maintains its own set of PCRs with their own validity periods — typically a few years, after which the rule is revised. Choosing the correct PCR at the start of the project avoids having to redo the calculation later.

Step 3 — third-party verification

This is where the real difference from an internal LCA lies. ISO 14025 requires a Type III declaration — the category to which EPDs belong — to be verified by an entity independent of both the manufacturer and the author of the study. The verifier re-performs checks on:

• the declared system boundaries and functional unit;
• the correctness of the inventory data and the characterisation factors used;
• compliance with the applicable PCR;
• the consistency of the documentation to be published.

Verification is not a bureaucratic formality — it is the reason an EPD can be cited in a public tender or towards a LEED or BREEAM credit, whereas an unpublished LCA cannot.

Step 4 — publication in the registry

Once verified, the EPD is uploaded to the portal of the chosen programme operator (EPD International, EPD Norge, IBU) and becomes public, with a unique registration code. Standard validity is five years from the date of verification; if the declared environmental impact deteriorates by more than 10%, the EPD must be updated before its expiry date. Renewal is normally started 6–9 months before the expiry date printed on the document, so that no coverage gap remains.

How long it realistically takes

The timeline almost always slips because of data collection from suppliers, not because of the calculation or the verification. Data collection should begin before the contract is signed, not after.

How CarbonDRI coordinates the process

CarbonDRI neither prepares the LCA alone nor verifies its own work — the structure is deliberately separated in order to preserve the independence required by ISO 14025:

• 01

  Project coordination

  CarbonDRI takes on the client request, defines the scope and the functional unit, and maintains contact between all parties involved.

• 02

  LCA/EPD preparation

  Carried out by specialised LCA practitioners who are partners of CarbonDRI.

• 03

  Independent verification

  Carried out by an accredited verifier, entirely separate from the team that prepared the study.

• 04

  Publication

  In the international registry relevant to the client’s target market (EPD International, EPD Norge or IBU).

This four-role structure is precisely what ISO 14025 requires for the credibility of an EPD — and the reason a published EPD carries far more weight than an internal report.

Frequently asked questions about LCA and EPD