An environmental product declaration (EPD) is a document describing the environmental impacts of a product such as a concrete mix, structural steel, or even architectural products such as carpet. EPDs are used by designers, owners, and regulators to compare products and determine the impact of a project. They also provide the information necessary to complete a Life Cycle Analysis (LCA), which is becoming more and more common.

They should be generated per ISO 14040/14044, ISO 14025, EN 15804, or ISO 21930 standards. ISO 14025 ensures verification by a third party, is very common, and often required. The data is collected and calculated according to standardized Product Category Rules defined in ISO 14025. EPDs are generally valid for 5 years from creation.

There are two main types of EPDs: Industry Average and Product Specific. An Industry Average Type III EPD is developed by industry organizations (AISC, NRMCA, etc.) and represents an aggregated environmental impact of the respective material, while a Product Specific Type III EPD is developed by a specific material manufacturer (Nucor, Vulcan, etc.) and measures the environmental impact of a single product.

The most basic information in an EPD is the global warming potential (GWP), measured in kilograms of CO2-equivalent (kg-CO2eq). This puts a number to the embodied carbon that can be allocated to a particular product. Whole Building Life Cycle Analyses, such as those now required by LEED v5, will also track additional impact categories that have other effects on the environment.

A great resource to find published EPDs in the DMV area is the Embodied Carbon in Construction Calculator (EC3) by Building Transparency. For more information, please reach out to any member of the SEA-MW Sustainable Design Committee.