AAC possesses excellent structural integrity, helping it to resist moisture penetration, whether caused by wind-driven rain or standing water. Additional weather and moisture resistance is achieved with a final surface treatment such as stucco, plaster and paint, or cladding such as bricks and/or other exterior materials.
Another benefit of an AAC wall is the approved stucco and acrylic finishes that are breathable while still being water resistant. Interior and exterior finishes have been formulated as one-way moisture barriers allowing vapor to escape thus preventing condensation, mildew and potential structural damage. In addition, cladding such as brick veneer, stone or siding may be applied to AAC walls.
AAC is not adversely affected by moisture and rot and is fully frost resistant, making its long term durability reassuringly predictable.
AAC's millions of tiny air pockets are not interconnected, which means the passage of water is severely resisted. The cellular nature of AAC, incorporating millions of pockets of trapped air, gives the product remarkable protection against frost. Tests have shown that AAC products have greater resistance to frost compared with traditional masonry products such clay bricks. As a matter of principle however, building materials should be protected against excessive wetting in severe winter climates.
ACCOA AAC is superior to normal concrete in water permeability because of its cellular structure and discontinuous microstructure. Tests conducted demonstrate the superior moisture resistance of walls constructed out of AAC blocks compared with traditional masonry products.