Brick calculator
Work out how many bricks you need for a wall, and the mortar to lay them.
Uses only the sizes you enter.
Result
You need 534 bricks for 9 square metres.
bricks
| Bricks in a square metre | 59.259 bricks |
|---|---|
| Mortar | 0.1585 m³ |
Show the workings
| Step | Sum | Answer |
|---|---|---|
| Space each brick takes, with its joint | 0.225 m × 0.075 m | 0.017 m² |
| Bricks in a square metre | 1 ÷ 0.01688 | 59.259 bricks |
| Bricks for the area | 9 m² × 59.259 | 533.333 bricks |
| Rounded up | 533.333 | 534 bricks |
| Mortar to fill the joints | 0.9225 m³ of wall − 0.764 m³ of bricks | 0.159 m³ |
Where the figures come from
This sum uses only the numbers you entered.
How many bricks in a square metre?
It depends on the size of the brick and the mortar joint. Add the joint to the brick's length and height, multiply them, and divide into one square metre.
For a brick 215 mm long and 65 mm high with 10 mm joints: (215 + 10) × (65 + 10) = 0.01688 m² a brick, so 1 ÷ 0.01688 = 59.259 bricks in a square metre of single-skin wall. Two skins need twice as many.
Bricks come in different sizes, so measure yours or check the pack before you order.
How much mortar?
Add the depth of your brick, front to back, and the calculator works out the mortar geometrically: the volume of the wall less the volume of the bricks in it. It does not allow for frogs or holes in the bricks, which take extra mortar, or for waste.