AAC In Depth

Autoclaved aerated concrete (AAC) is a lightweight, precast concrete building material suitable for producing concrete masonry units (CMU) like blocks. Composed of quartz sand, calcined gypsum, lime, cement, water, and aluminum powder, AAC products are cured under heat and pressure in an autoclaved. Invented in the mid-1920s, AAC simultaneously provides structure, insulation, and fire- and mold resistance. Forms include blocks, wall panels, floor and roof panels, cladding (façade) panels, and lintels.

AAC products may be used for interior and exterior construction. For example, they may be painted or coated with a stucco or plaster compound to guard against the elements or covered with siding materials such as veneer brick or vinyl siding. In addition to their quick and easy installation, ACC materials can be routed, sanded, or cut to size on-site using standard power tools with carbon steel cutters. Please see more on our interior/exterior finishes page or our electric/plumbing installation page for additional techniques and applications.

Besides AAC's insulating capability, one of its advantages is quick and easy installation because the material can be routed, sanded, or cut to size on-site using standard power tools with carbon steel cutters.

AAC is well suited for high-rise buildings and those with high-temperature variations. Due to its lower density, high-rise buildings constructed using AAC require less steel and concrete for structural members. The mortar needed for laying AAC blocks is reduced due to the lower number of joints. Similarly, the material required for rendering is also lower due to the dimensional accuracy of AAC. The increased thermal efficiency of AAC makes it suitable for use in areas with extreme temperatures, as it eliminates the need for separate materials for construction and insulation, leading to faster construction and cost savings.

Even though regular cement mortar can be used, most codes in buildings erected with AAC materials use thin bed mortar in thicknesses around ⅛ inch, depending on the national building codes. In addition, AAC materials can be coated with a stucco or plaster compound to guard against the elements or covered with siding materials such as brick or vinyl.