CMHA releases first U.S. Industry-Average EPD for concrete masonry units

Sources: Concrete Masonry & Hardscapes Association, Herndon, Va.

The Concrete Masonry & Hardscapes Association (CMHA) provides global warming potential (GWP) and other requisite metrics for seven light, medium or normal weight block classes in the premier Industry-Average Environmental Product Declaration (EPD) for Concrete Masonry Units in the United States. Leading EPD author Climate Earth Inc. factors data from 35 CMU producers in the ASTM International-verified document.

The Industry-Average EPD for CMU charts GWP figures—kilograms of carbon dioxide equivalents (kg CO₂e) —by cubic meter of mix for each block class, ranging from 208 kg CO₂ e for normal weight block (2,000-3,240 psi compressive strength; density ≥ 125 pcf) to 395 for lightweight block with expanded shale, clay or slate manufactured aggregate (2,000-4,490 psi compressive strength; density ≤ 104.9 pcf). The figures reflect downward adjustments for estimated natural carbon sequestration volumes at 28 days, the EPD’s “at the gate” threshold or system boundary. They range from 18 kg CO₂e to 22 kg CO2 e, respectively, for normal weight block of conventional (2,000-3,240 psi) and higher (≥ 4,500 psi) compressive strength mix designs. As supplemental information, the EPD cites estimated carbon sequestration volumes at two years, where the kg CO₂e is at least double the 28-day figures.

“The publication of the first United States EPD for CMU is a significant accomplishment for the industry,” says CMHA CEO Bob Thomas. “Members are committed to sustainability, and this EPD accurately quantifies environmental impacts. These results can be used to inform building materials environmental databases, influence decisions on building materials, and ensure that concrete masonry is seen as a sustainable building solution.”