AAC (Autoclaved Aerated Concrete) is one of the most widely used wall materials in the world, but it is not universal. As a supplier with 10+ years of experience, we honestly break down all the pros and cons of this material so you can make an informed decision.
Pro 1 — Lightweight. AAC density is only 400–700 kg/m³, 3 times lighter than brick and 5 times lighter than concrete. Lower building weight means a cheaper foundation, reduced seismic load, and the ability to build on weak soils. One AAC block (600×250×200 mm) weighs 12–15 kg and can be carried by one worker, while the equivalent volume of brick weighs 40–50 kg.
Pro 2 — Thermal insulation. The closed porous structure of AAC provides a thermal conductivity coefficient of only 0.09–0.16 W/m·K, compared to 0.7–0.8 for brick and 1.5 for concrete. In cold climates, this means thinner walls for the same thermal resistance: brick requires 770 mm (2.5 bricks), AAC only 300–400 mm. Thinner walls = more usable floor area.
Pro 3 — Fire resistance and sound insulation. AAC is a non-combustible inorganic material (NG group), fire resistance limit 3–6 hours at 100–200 mm thickness. Sound insulation of a 200 mm AAC wall is 40–50 dB, meeting residential building requirements. The material does not rot, is not affected by rodents or insects.
Pro 4 — Installation speed and eco-friendliness. Large AAC blocks (600×250 mm) are laid 2–3 times faster than brick. AAC production uses fly ash and quartz sand, is 30% more energy efficient than brick, and has no radioactivity. Con 1 — Strength and fixing. AAC compressive strength is only 2.5–7.5 MPa, the material is not suitable for load-bearing walls (a frame structure is required). Limited fixing capacity: heavy items (water heaters, air conditioners) require special anchors or embedded elements.
Con 2 — Moisture absorption and brittleness. AAC water absorption can reach 30%, so exterior walls require mandatory water-repellent finishing (tile or render). The material is relatively brittle, prone to corner chipping during transport and installation, requiring careful handling. Conclusion: AAC is ideal for non-load-bearing partitions and exterior walls in frame buildings, especially in cold climates and high-rise construction. But it requires proper installation technology and complementary materials.
