The Environmental Protection Agency (EPA) is setting up a program to rate construction materials by their climate impacts. Suppliers of materials with lower impacts – with reduced emissions of climate warming gases associated with their production (also called embodied carbon) – will be able to apply an EPA “low embodied carbon” label to their products. Their products will be listed in an EPA registry of low-carbon construction products.
Congress directed the EPA to set up this program in the Inflation Reduction Act of 2022, with the intent of mitigating climate change by directing federally funded purchases of construction materials to those materials with the lowest climate impacts. The Biden Administration intends to require infrastructure owners using federal funds – including state Departments of Transportation (DOTs), but also, for example, municipal drinking water and wastewater utilities using the EPA’s revolving loan programs – to use only the construction materials identified by the EPA as having low embodied carbon.
Is this good or bad for manufacturers of composite construction products? No surprise, it will depend on how the EPA implements the program.
It would be very good for composites, for example, if the EPA’s program encourages comparison, early in a project’s design, of the full lifecycle impacts of functionally equivalent materials and products. Composites manufacturers have long wanted state DOTs and other infrastructure owners to consider products like composite rebar early in the design of a project. The expected service life of composite rebar exceeds the typical 100-year design lifetime of a highway bridge, while traditional materials will likely need to be replaced long before that time even if properly maintained. Both the emission of climate warming gases and costs can be reduced when composite products are used in an infrastructure project.
ACMA asked Hota GangaRao, director of the Constructed Facilities Center at West Virginia University (WVU), Yoojung Yoon, an associate professor at the university, and their colleagues at WVU to compare emissions of climate warming gases associated with traditional steel products with emissions associated with functionally equivalent composite products. One of the products studied by the researchers is a girder (beam), such as one that might be used to support a bridge deck. They compared a steel beam of a standard design and a composite beam that is functionally equivalent, meaning it has the same deflection under load and other properties important to its function in the application. A preliminary analysis of these products concludes that, over the 100-year design lifespan of a bridge, use of the steel beam would result in the emission of seven times more climate warming gases than if the composite beam was used.
Unfortunately, the EPA’s Feb. 15, 2024, proposed approach to the embodied carbon labeling program would do nothing to encourage this kind of comparison. The EPA intends, at least initially, to evaluate only the production-phase climate impacts of a limited number of traditional construction materials, such as steel and concrete. And the EPA wants infrastructure designers to refer to the embodied carbon labeling program only after the design phase of a project when it has already been decided whether to use a traditional material like steel.
ACMA argued in comments provided to the EPA that the agency’s label program should facilitate the comparison of functionally equivalent steel and composite products at the design stage, since for many infrastructure applications this approach will achieve a significant reduction in emission of climate warming gases and more fully satisfy the intent of both Congress and the Biden Administration to achieve the largest possible emission reductions.
While the EPA reviews public comments to further develop the construction materials embodied carbon labeling program, ACMA will continue to provide resources to help composites manufacturers communicate to end users the full lifecycle benefits of their products, including the preparation of product category rules, development of a generator that manufacturers of composite construction products will use to reliably and cost effectively prepare lifecycle analyses and environmental product declarations (EPDs), and the program on functionally equivalent construction products described above. For more information on these resources, check out the feature article on page 20.
John Schweitzer is vice president of EH&S and sustainability at ACMA. Email comments to jschweitzer@acmanet.org.
