How to Calculate Bricks for a Wall
Learn the exact formula for calculating how many bricks you need for any wall, including mortar and wastage allowance.
Why Accurate Brick Estimation Matters
Over-ordering bricks wastes money; under-ordering causes costly project delays. A precise estimate accounts for the brick size, mortar joints, and a 5% wastage factor for breakage and cuts.
Standard Brick Dimensions
A standard brick measures 225 mm × 112.5 mm × 75 mm with a 10 mm mortar joint on all sides. The effective laid size is therefore 235 mm × 122.5 mm × 85 mm.
The Formula
For a single-brick-thick wall:
Bricks per m² = 1 / (0.235 × 0.085) ≈ 50 bricks/m²
For the full wall:
Total bricks = Length × Height × 50 × thickness_factor × 1.05
Where thickness factor is 1 for a half-brick wall, 2 for a single-brick wall, and 4 for a double-brick wall.
Mortar Estimation
A general rule of thumb: one 25 kg bag of mortar covers approximately 125 bricks. So:
Mortar bags = Total bricks ÷ 125 (rounded up)
Example Calculation
For a wall 5 m long × 3 m high, single brick thick:
- Area = 5 × 3 = 15 m²
- Bricks = 15 × 50 × 2 × 1.05 = 1,575 bricks
- Mortar bags = 1,575 ÷ 125 = 13 bags
Use Our Free Brick Calculator
Save time by using our online brick calculator — just enter your wall dimensions and get instant results.