Getting to an EPD is a regimented process, with checks and third-party verifications along the way. There has to be consistency in process and definitions to create a standard vocabulary for all products that pursue an EPD. That is where PCRs, or product category rules, come into play. A PCR defines the rules and requirements for EPDs in a certain product category.
“An LCA of a product must be conducted according to the previously published PCR for the type of product being assessed. If a PCR doesn’t already exist, those rules must first be developed by an editing committee with stakeholder participation and external review,” Mandlebaum says. “Once the LCA has been conducted, it may require a peer review. After peer review, the EPD is developed by formatting the LCA results to fit EPD requirements. This step requires verification by a program operator, which is a separate entity who can write and house PCRs, as well as verify an EPD and its associated LCA conform to the necessary standards. Once verified by the program operator, an EPD can be published and communicated.”
When established, EPDs can be helpful to owners and designers making choices about their buildings. “When an architect or design team reads an EPD for a product, they will find information that is most important to them,” Kriner says. “Comparison among other products’ EPDs can guide a design team to evaluate the most desirable product based on a particular environmental impact category. For LEEDv4 registered projects, there are points available in credits within the Materials and Resources category for products used in the building that have industry-wide EPDs or product-specific EPDs.”
“If a company provides an EPD for its product, that means the company has committed to measuring, and hopefully reducing, the environmental impact of its product over its full life cycle and is disclosing that information in an accurate and credible way,” Mandlebaum says. “While there may be some value in comparing the outcomes of different products on the basis of EPDs, this should be approached with some care. Even though EPDs are based on standards, there is still some potential for variability that is due to how the assessment for each product is conducted, rather than due to the actual differences in the products and their production.”
Though an EPD can never be perfect enough to completely summarize a product, the effort to disclose as much information and empower those making the decisions with as much information as possible has been very positive. “Transparency in building products is becoming more important to the design community,” Kriner says. “That can mean transparency in the environmental impact of materials used, as well as the types of chemical ingredients in various building materials for the health and wellness of occupants. This trend is expected to increase in importance, making EPDs even more prevalent.”
“EPDs do appear to be becoming more prevalent in a variety of industries. This is usually driven by demand from customers for these documents, complemented by a desire to build a competitive advantage,” Mandlebaum says. “In the case of building products, there are rating systems like LEED [from the U.S. Green Building Council, Washington, D.C.] that are driving demand for EPDs by favoring products that have these declarations available. In some parts of the world, governments are driving the demand for EPDs. For example, in the European Union, there is an experimental program in place that would facilitate the voluntary reporting of EPDs across a wide range of industries.”
The roofing industry in the U.S. has generated a number of LCAs, PCRs and EPDs (see “EPDs Up On the Roof”, page ), and the trend seems to indicate more will be coming. With more EPDs available, it is important to understand how the information should be applied.