Why do EPDs get stuck in verification?
Publishing an Environmental Product Declaration (EPD) is a massive step forward in your company's sustainability journey. But let’s be honest — getting through the mandatory third-party verification process can sometimes feel like running an obstacle course. At EPD Hub, we review a large number of Life Cycle Assessment (LCA) models, and over time, we’ve noticed that most verification delays boil down to a few specific challenges. To make your next EPD verification a much smoother process, you will first need to understand these technical roadblocks.
The data quality dilemma
The most common reason EPDs are returned for revision is data quality. An EPD is only as good as the data behind it, which means verifiers need to see the full picture. This requires clear, comprehensive documentation of your product recipes, allocation procedures, and exact total annual values for energy, waste, and ancillaries. So for example, when you are using secondary data from background databases, it is crucial that the information is truly representative of your product and complies with your selected reporting standards, such as EN 15804+A1 or +A2. You also need to watch out for mismatched indicators to avoid data inconsistencies, like misalignments between the abiotic depletion of primary fossil fuels and primary energy. Ultimately, performing a strict data quality assessment before you submit your EPD is your best defense against these data-driven delays.
Vague assumptions and "green" language
Another major hurdle that we have seen involves vague assumptions and the temptation to use subjective marketing language. We all want our products to sound fantastic, but an EPD is a scientific, standardized document. Your product description must be highly specific, including exact technical characteristics and performance standards. It also needs to provide a clear explanation of your LCA assumptions to prove the model is complete and accurately accounts for all materials and processes in every single life cycle stage. Remember, the rigorous process involved with EPD verification is what sets this form of environmental declaration apart from all the other sustainability claims out there. This is why verifiers will immediately red-line subjective claims and terms like "low carbon," "environmentally friendly," or "green", which are simply not allowed in an EPD unless you have a separate, third-party verification explicitly declaring that specific claim. Keeping your language completely objective and factual will save you a lot of back-and-forth during the review process.
The modeling maze
Finally, modeling specific life cycle stages can easily get tangled up, especially when dealing with electricity, carbon balancing, and end-of-life scenarios. For example, in the manufacturing stage (Module A3), we require a market-based approach for electricity. So if you are claiming to use renewable energy, then you must back it up with documented contracts, Guarantees of Origin, or proof of your own on-site production. Alongside energy, biogenic carbon—the carbon stored in biological materials—must be perfectly balanced and reported according to the PCR for each specific stage and material type. This is where the EN 16449 standard will provide guidance on whether or not a material is combustible, so that you are correctly calculating its carbon content. This also ties into the end of your product's life, where your chosen waste scenarios in Modules C3 and C4 must make logical sense and match up perfectly with the benefits and loads you claim beyond the system boundary in Module D. Applying accurate net-flow calculations is essential here, meaning you cannot claim recycling benefits at the end if you haven't correctly modeled the recycling scenarios in the first place.
The main point to remember here is that verification doesn’t have to be a headache. By double-checking your data, keeping your descriptions objective and ensuring your energy and end-of-life models follow the rules, you can speed up the process significantly.
