Autoclaved Aerated Concrete

Autoclaved aerated concrete, often abbreviated AAC, is a lightweight cementitious building material produced by mixing cement, lime, sand or fly ash with a foaming agent, typically aluminum powder, that generates tiny gas bubbles throughout the mix, and then curing the resulting porous block under high-pressure steam in an autoclave. First developed in Sweden in the 1920s, it is roughly a fifth the density of ordinary concrete, giving it strong thermal insulation properties alongside structural load-bearing capacity, and its lightness, ease of cutting and fire resistance have made it a popular masonry unit for both structural walls and non-structural partitions, particularly across Europe and increasingly elsewhere.