Introduction: The Most Misused Number in an EPD
Module D reports the benefits and loads beyond the system boundary — the recycling and recovery credits. It is also the figure most often misread, mis-netted and over-claimed. Here is how to handle it correctly.
In an EN 15804 EPD, the life cycle runs through production (A1–A3), construction (A4–A5), use (B) and end of life (C). Then, reported separately, comes Module D: the net environmental benefits and loads beyond the system boundary, from reuse, recovery, recycling and exported energy. Module D is where the “recycled steel is green” story lives — and where most mistakes are made.
What Module D Actually Is
Module D credits (or charges) the product for what happens to its materials and energy after the assessed system: the avoided burden of producing virgin material that recycled output replaces, recovered energy, and so on. Crucially, EN 15804 requires it to be declared as a separate module, never folded into the A1–A3 product figure.
Five Ways It Gets Used Wrong
| The mistake | Why it is wrong |
|---|---|
| Subtracting D from A1–A3 to show a lower “product footprint” | D is reported separately; netting it into the cradle-to-gate number is not permitted and flatters the result |
| Double-counting recycled content | Claiming both the recycled-input benefit in A and the end-of-life recycling benefit in D for the same material |
| Comparing products on D | D depends on end-of-life scenarios and assumptions that differ between EPDs; the comparison is not like-for-like |
| Optimistic end-of-life scenarios | Assuming near-total recycling or reuse that real waste streams do not deliver |
| Treating D as a carbon offset | D is a modelled avoided burden, not a purchased offset or a neutrality claim |
How to Read It Correctly
Look at A1–A3 (and A–C) first — that is the product’s assessed footprint. Treat Module D as informational and scenario-dependent: useful for circularity insight, but not a discount on the product number. Check the end-of-life assumptions behind D before you give it any weight, and never accept a single headline figure that has already netted D into A.
What This Means for Buyers and Specifiers
If a supplier presents one impressively low number, ask whether Module D has been blended into it. Insist on seeing A and D separately. The same discipline that protects you here is exactly what an experienced reviewer applies — see our guide on how to read an EPD like an auditor.
How EPD Polska / Multicert Can Help
We prepare and verify EPDs that report Module D transparently and correctly, and we help buyers interpret third-party EPDs without being misled by a netted number. Contact us for an EPD reviewed properly.
FAQ
Can I add Module D to A1–A3 to get a net figure?
No. EN 15804 requires Module D to be reported separately. Presenting a single A-minus-D number misrepresents the product’s assessed footprint.
Is a large Module D credit a good sign?
Not by itself. It reflects modelled end-of-life assumptions that may be optimistic; check the scenario before relying on it.
Does Module D help with CBAM?
No. CBAM looks at production emissions, not end-of-life recycling credits. Module D is an LCA construct, not a CBAM input.