What is AAC Technology?
Autoclaved Aerated Concrete (AAC) is a lightweight, precast building material that offers superior performance for modern construction.
Understanding AAC
Autoclaved Aerated Concrete (AAC) is an innovative building material invented in Sweden in 1924. It is manufactured by mixing sand, cement, lime, water, and an expansion agent (aluminum powder).
The mixture is poured into molds where the aluminum reacts to create millions of tiny air cells, giving AAC its characteristic lightweight and insulating properties. The material is then cured in autoclaves under high pressure and steam.
The result is a building material that combines the workability of wood with the strength and durability of concrete, offering exceptional thermal and acoustic insulation.
Composition of Aerated Concrete
Our AAC products are manufactured using proven technology with high-quality natural components.
Cement
High-quality Portland cement serves as the main binding component that ensures the strength of the blocks.
Sand
Finely ground quartz sand serves as a filler and gives the block resistance to loads.
Lime
Slaked lime participates in chemical reactions that promote the formation of pores.
Water
Used to hydrate the cement and mix the components.
Aluminum Powder/Paste
A gas-forming component that reacts with lime to form pores through hydrogen release.
Chemical Properties
The unique properties of AAC arise from carefully controlled chemical reactions during manufacturing.
Gas Formation
Aluminum powder reacts with calcium hydroxide, releasing hydrogen which creates millions of small pores in the mixture.
Tobermorite Formation
During autoclaving, calcium combines with silicohydrate to form tobermorite - a mixture of crystalline, semi-crystalline, and amorphous structures that gives AAC its strength.
Environmental Safety
The use of natural components makes the material safe for the environment and human health.
Fire Resistance
The inorganic composition makes aerated concrete a fire-resistant material resistant to high temperatures.
Fire Safety
Aerated concrete is considered one of the most fire-safe building materials. It belongs to the class of non-combustible materials (class NG).
- Can withstand high temperatures for extended periods without losing strength and load-bearing capacity
- Creates a reliable barrier preventing fire spread to other rooms
- Blocks retain their shape even at +900°C and can be reused after minimal fire damage
Density Grades & Specifications
AAC is available in various density grades, each suited for different applications. Lower density provides better insulation, while higher density offers greater strength.
| Density Grade | Density (kg/m³) | Compressive Strength (kg/cm²) | Thermal Conductivity W/(m·°C) | Frost Resistance (cycles) | Strength Class |
|---|---|---|---|---|---|
| D200 | 200 | 10-15 | 0.048-0.058 | 25 | B0.75-B1.0 |
| D300 | 300 | 15 | 0.072-0.084 | 25 | B1.5-B2.0 |
| D400 | 400 | 25 | 0.096-0.117 | 35 | B2.0-B2.5 |
| D500 | 500 | 35-46 | 0.120-0.147 | 50 | B2.5-B3.5 |
| D600 | 600 | 46 | 0.144-0.183 | 75-100 | B3.5-B5.0 |
* D400-D500 grades are most commonly used for load-bearing walls in residential construction
Key Benefits of AAC
AAC offers numerous advantages that make it ideal for residential and commercial construction.
Energy Efficiency
AAC has excellent thermal insulation properties with thermal conductivity ranging from 0.048 to 0.183 W/(m·°C) depending on density, reducing heating and cooling costs significantly.
Fire Resistance
AAC belongs to the class of non-combustible materials (class NG). It does not ignite even at +900°C, does not support combustion, and does not emit toxic gases. Blocks retain their shape and can be reused after fire if damage is minimal.
Sound Insulation
The porous structure of AAC provides excellent acoustic insulation, reducing noise transmission between rooms and from external sources.
Moisture Control
AAC regulates humidity levels naturally, absorbing excess moisture and releasing it when the air is dry, creating comfortable indoor environments.
Eco-Friendly
Made from natural components (cement, sand, lime, water, aluminum), AAC is environmentally friendly and safe for human health with low carbon footprint in production.
Lightweight
With density ranging from 200-600 kg/m³, AAC is significantly lighter than conventional concrete, reducing structural load requirements and foundation costs.
Technical Characteristics
| Density Range | 200-600 kg/m³ |
| Compressive Strength | 10-46 kg/cm² |
| Thermal Conductivity | 0.048-0.183 W/(m·°C) |
| Frost Resistance | 25-100 cycles |
| Fire Class | NG (Non-combustible) |
| Max Temperature Resistance | +900°C |
Technical Excellence
AAC meets rigorous international standards and offers consistent, predictable performance in construction applications.
The material's cellular structure provides an optimal balance of strength, weight, and insulation properties, making it suitable for load-bearing and non-load-bearing applications.
AAC can be easily cut, drilled, and shaped on-site using standard woodworking tools, reducing construction time and labor costs.
Ready to Use AAC in Your Project?
Explore our range of AAC products or contact our technical team for expert advice.