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Traditional bricks in the construction sector are quickly being replaced by AAC blocks, also known as autoclaved aerated concrete blocks. AAC is a foam concrete material up to three times more lightweight than ordinary bricks, making it simple to handle and put to use.

AAC is a familiar construction material in the industry. Instead, it came into being sometime during the 1920s. However, it became popular only in the past decade. If you are building a house, you should consider using AAC blocks rather than red bricks.

How are AAC blocks made?

 AAC blocks are lightweight because of their porous, foam-like surfaces. Components like cement, water, sand, and lime are utilised to construct these blocks. Additionally, a tiny amount of raising agent is added, which helps create the porous structure.

Burnt clay bricks and AAC blocks are manufactured differently and use different ingredients. To make the AAC block construction lightweight and durable, it is autoclaved. An autoclave is a machine that can set high pressure and temperature to produce superheated steam. 

Now, as the AAC is blended and cast, other substances are added to improve the properties of the AAC blocks. Calcium hydroxide and aluminium powder are combined, releasing water and hydrogen gas. The porous, foam-like structure that is produced at the end is primarily due to the frothing up of this gas. The completed structure is up to three times lighter than a typical cement block because the gas rises to a height of 3mm inside the mixture.

It takes the mixed slurry roughly 10 to 12 hours in the autoclave chamber to solidify. The sizes of AAC blocks are largely uniform worldwide. The price and the weight of the AAC block depend on the size you choose. Most often, people choose a size 600mmX 200mmX200mm. These blocks can weigh up to 15 kg each.

Here are some advantages of using the AAC blocks for your home construction-

1. Durability - AAC blocks are renowned for their exceptional strength, which provides more stability to the structure of a building, thus increasing the dependability and seismic resistance of that building. Another point to note is that non-biodegradable components are used in the production of the AAC material, increasing its mould resistance and resulting in better, cleaner, and more durable interiors.

2. Faster Construction - The blocks made with AAC can be cut using ordinary instruments like drills, band saws, etc., because the material is relatively simple to handle and control. Because the labour force won't need any specialised skills, this makes construction simpler and more resource-efficient. Additionally, the AAC blocks are nine times larger than red clay bricks, resulting in fewer joints throughout the framework of the building. This can immediately affect how long it takes to complete the construction. Not only that, but it also means less brickwork will be needed, which will shorten the project's completion time. In general, using AAC blocks reduces construction time by 20%.

3. Thermal Insulation - The structure's interior can stay warm in cold weather and cool in hot weather thanks to the thermal conductivity of the AAC blocks. This immediately affects the amount of energy used for air conditioning and results in cost savings of up to 30%, making it a more energy-efficient option than any other material.

4. Cost saving - Fundamentally, AAC blocks weigh far less than conventional red bricks, which can directly impact the quantity of cement and steel used in building, making it a more cost-effective solution. Since this material is produced using an automated method, the finished blocks are more precise and smoother, negating the need for three coats of plaster on walls. The weight is a third of a standard red clay brick structure, which results in a 15% reduction in steel utilisation and cost savings.

5. Sound and Fire resistant - Because AAC Blocks are manufactured with a porous structure, they have excellent sound absorption qualities. AAC Blocks are the ideal material for building walls because of their Sound Transmission Class (STC), which is about 45 dB. AAC Blocks have the best fire resistance in its class, with a fire rating of 4-6 hours. With a melting point of over 1600 °C compared to the red clay bricks' 900 °C, the block's cellular structure renders it fire-resistant.

6. Versatility - AAC blocks can be made in any size, shape, and strength to complement the architecture of your building. AAC blocks are more adaptable for builders and end users since they are easier to chisel and plumb than solid concrete blocks and red clay bricks.

 7. Environment friendly - While red clay brick production uses top layer soil, which makes it less suited for plants, AAC blocks are built utilising 70% fly ash, a national waste. Compared to other processes, the production process uses very little energy. Additionally, no contaminants, byproducts, or hazardous waste are produced during the procedure.

The combination of all these benefits makes AAC blocks the preferred choice for construction in the future. We won't be mistaken if we say that in the near future, we'll witness many more buildings and structures created using this material in India and worldwide. The demand for lightweight building materials is rising, and the trend toward green buildings is fueling this expansion.