E-CRETE. This company’s autoclaved aerated concrete block is a solid, high-performance masonry unit made with a low-energy process that emits no pollutants and creates no by-products or toxic waste products, according to the manufacturer. The finished block is resource-efficient, measuring twice the volume of the raw materials used, and its light weight can help reduce seismic mass and dead load design requirements. AAC block meets ASTM specifications for load-bearing compression, fire resistance, sound transmission, and more, and can contribute to LEED design. 866.508.5803. www.e-crete.com.