AAC Block & Adhesive Calculator

AAC Block Calculator: Estimate Siporex Blocks & Adhesive

Autoclaved Aerated Concrete (AAC) blocks are rapidly replacing traditional red clay bricks in modern Indian construction. Because they are up to 3 times lighter, they reduce the dead load on RCC structures and speed up construction. Use our AAC block calculator to accurately estimate the number of blocks and the chemical adhesive required for your project.

How to Calculate AAC Blocks

Unlike red bricks which vary wildly in size, AAC blocks (often known by the popular brand name, Siporex) are manufactured in standard, precise dimensions. The standard face size of an AAC block in India is 600 mm (Length) × 200 mm (Height). The only dimension that changes is the thickness (typically 100mm, 150mm, or 200mm).

The "Blocks per Sqm" Rule

Because the face of the block is always 600mm x 200mm, calculating the number of blocks per sqm is incredibly straightforward.

• Face Area of 1 Block = 0.6m × 0.2m = 0.12 sqm.
• Blocks per Square Meter = 1 sqm ÷ 0.12 sqm = 8.33 Blocks per sqm.

Note: When we account for the 3mm adhesive joint, it drops slightly to roughly 8.22 blocks per sqm.

Siporex Block Calculation Example

Let’s walk through a practical Siporex block calculation for a wall measuring 10 feet long by 10 feet high, using 200mm (8-inch) thick blocks.

Why Chemical Adhesive instead of Cement Mortar?

AAC blocks are highly porous and absorb water quickly. If you use traditional cement-sand mortar, the blocks will suck the moisture out of the mortar, causing the joints to crack and fail.

Instead, a specialized thin-bed polymer chemical adhesive is used. It only requires a 2mm to 3mm joint thickness.

Adhesive Calculation Thumb Rule:

In the Indian construction industry, a standard 40 kg bag of block adhesive is sufficient to lay approximately 1.2 Cubic Meters (m³) of AAC masonry. Our calculator automatically determines your total wall volume and divides it by 1.2 to tell you exactly how many 40kg bags you need to order.