Autoclaved Aerated Concrete Autoclaved aerated concrete (AAC) is made with fine aggregates, cement, and an expansion agent that causes the fresh mixture to rise like bread dough. In fact, this type of concrete contains 80 percent air. In the factory where it is made, the material is molded and cut into precisely dimensioned units.
-
Durability and dimensional stability. A cement-based material, AAC resists water, rot, mold, mildew, and insects. Units are precisely shaped and conform to tight tolerances.
- Fire resistance is excellent, with eight inch thick AAC achieving a four-hour rating (actual performance exceeds that and meets test requirements for up to eight hours). And because it is noncombustible, it will not burn or give off toxic fumes.
- The light weight means that R-values for AAC are comparable to conventional frame walls, but they have higher thermal mass, provide air tightness, and as just noted, are not combustible. That light weight also gives a high sound reduction for privacy, both from outside noises and from other rooms when used as interior partition walls.
