AAC Block Calculator
Home & ConstructionBlocks, thin-bed adhesive and wall weight for AAC masonry, compared against the same wall in brick.
Runs entirely in your browser — nothing is uploaded
AAC differs from brickwork in one respect that changes the whole estimate: it is laid in a 2–3 mm bed of thin-bed adhesive rather than a 10–12 mm bed of cement mortar. That means the block count is close to the geometric count and the jointing is measured in bags of adhesive. This works out both, and shows the wall weight against the same wall in brick — the saving that justifies AAC in the first place.
What people do next
Features
- Every standard block thickness from 75 mm to 300 mm.
- Thin-bed adhesive in kilograms and 40 kg bags, or conventional cement mortar.
- Wall weight compared with the same wall in burnt clay brick.
- Three density grades, from lightweight to structural.
- Wastage allowance and cost at your own rates.
- Calculated in your browser — nothing is uploaded.
How to use the AAC Block Calculator
- 1Enter the wall length and height — the face, not the thickness.
- 2Choose the block size and grade.
- 3Pick thin-bed adhesive or cement mortar for the joints.
- 4Read the block count, the jointing material and the weight saved.
Frequently asked questions
How many AAC blocks are in a square metre?
About 8.2 for the standard 600 × 200 face with a 3 mm joint — each block covers 0.1224 m² including its share of the joint. The thickness does not change the count, only the volume and the weight, because every Indian AAC block has the same 600 × 200 face.
How much adhesive does AAC blockwork need?
Roughly 25–35 kg per cubic metre of masonry for a 3 mm joint, sold in 40 kg bags. A 100 m² wall at 200 mm thick is 20 m³, so about 600 kg or 15 bags. Manufacturers publish their own consumption figure and it varies with block flatness and workmanship — use theirs if you have it.
Can AAC blocks be laid in ordinary cement mortar?
They can, and on many sites they are, but it costs you much of the reason for choosing AAC. A 12 mm cement mortar bed conducts heat far better than the block either side of it, so thick joints create thermal bridges through the wall and undo a good part of the insulation. They also use a great deal more material. The tool shows both so the difference is visible.
How much lighter is an AAC wall than a brick wall?
About two thirds. AAC is 550–650 kg/m³ for the common structural grade, against roughly 1,900 kg/m³ for brick masonry — so a 100 m² wall at 200 mm thick weighs about 12 tonnes in AAC against 38 tonnes in brick. That is 26 tonnes of dead load the beams, columns and foundations do not have to carry, which is where the real saving on a framed building comes from.
Do AAC walls need plaster?
Yes, though less of it. AAC is dimensionally accurate enough that a thinner coat suffices, and many jobs use a gypsum plaster internally rather than cement. Chicken mesh at the junction with columns and beams is worth insisting on — that interface is where AAC walls crack.