This article summarizes the key rules for product averaging and similarity for different EPD programs. The EPD programs may update their rules at any time without notice, and this article can not be guaranteed to be up to date. For any specific case, please request One Click LCA to confirm the matter for your specific product(s).
Rules for determining if products are similar EPD Hub
Products are in the same group, when they are manufactured using same process and raw materials and are used for same or highly similar purpose, and have same use phase and same end of life treatment scenario. Description on similarity of products is provided in the EPD Hub GPI in Annex I “Rules for averaging and aggregating EPDs”. However, similar products are not subject to the limitations of GWP variability.
Rules for determining if all EPD are in a single group or several for the International EPD System
Products are in the same group, when they are manufactured using same process and raw materials and are used for same or highly similar purpose, and have same use phase and same end of life treatment scenario. Having multiple groups of products in a single EPD submission requires a third-party verification of each underlying different LCA model, and hence carry additional cost. If a c-PCR is used, all must use the same c-PCR. Following rules can be used to ensure if all products are in the same group:
Products with different dimensioning or sizing, for example all structural elements or sizes of any variable size elements, having same function, constituents and purpose, would always be considered to be in the same group. For example, all structural precast concrete elements with reinforcement steel would be considered to be in the same group.
Products mixed from same raw materials (for those having 5+ % of mass or GWP-GHG), where share of the raw materials varies by product. This would apply for example to most ready-mix concretes, barring special mixes and products such as shotcrete or fibre-reinforced concrete. Differences in strength class of the same product would be same product group.
Products assembled from same raw materials (for those having 5+ % of mass or GWP-GHG), where thickness or spacing of elements varies by product. This would apply for example to most sandwich elements, windows or doors. For assembled products, replacing an element in the assembly with entirely different type of element is allowed in a group.
If any of the products has different c-PCR, different purpose, different use phase or end of life treatment scenario or is manufactured in a very different way, it shall be considered to be from a different group. For example, ready-mix concrete and precast concrete elements are considered to be different groups, as are steel sandwich elements and structural steel elements.
Rules for averaging EPDs for the International EPD System and RTS
Detailed rules applying to averaging are as follows (and they vary somewhat between EPD programs):
Averaging is only possible for products that are similar (manufactured using a similar process from similar raw materials).
For assembled products, the components may vary significantly, but the intended use of product must be same (e.g., single EPD can only contain either external windows or internal doors).
Every averaged EPD must mention every product, location and manufacturer it represents.
For RTS: Different products, sites and manufacturer can be averaged in a single EPD, if difference in GWP-total (+A2) is within 10 % (10 % from the lowest value to the highest). Different sites of same manufacturer can be averaged using annual volumes into a single set of LCA results, if difference in GWP-total (+A2) is no more than 35 %. (Guideline 2.1.1).
For the International EPD System, unless otherwise is confirmed separately, different products/sites of same manufacturer, or different manufacturers can be averaged into a single result, if the difference in GWP-GHG is <10%. Variations to this are only possible on separate written confirmation; in such cases documentation of range of variance for the GWP-GHG is required on the EPD (PCR 4.6).
There is one exception: an EPD can cover up to five products that do not need to be averaged if the inputs within the LCA scope are invariable (inside the cut-off criteria), including the REACH SVHC materials, and product description and associated textual information. In this case they do not require separate inspection.