Quantities
Facing brick quantity
- where
- bricks per square metre
- brick length (mm)
- perpend joint (mm)
- brick height (mm)
- bed joint (mm)
- net area (m²)
- waste allowance (%)
Explain this equation
This estimates how many facing bricks to order for an area of a single stretcher-bond leaf, including waste.
l and h are the actual brick length and height in mm. j_p is the perpend (vertical) joint and j_b the bed (horizontal) joint. Each brick with its joints takes up (l + j_p) × (h + j_b) of face, and N_m² is how many fit in a square metre. A is the net wall area and w the waste percentage.
A square metre is 1 000 000 mm², so dividing that by the face each brick occupies gives bricks per m². Multiplying by A gives the net count, and (1 + w/100) adds the waste. The ⌈ ⌉ brackets mean round up, because you cannot order part of a brick.
A 215 × 65 mm brick with 10 mm joints occupies 225 × 75 mm, giving about 59.3 per m², usually called 60. Ten square metres with 5% waste comes to 623 bricks.
Watch out: this is an area estimate. Specials, piers, returns, cuts and bond patterns that are not stretcher bond need a separate take-off.
Estimate one stretcher-facing leaf using actual unit sizes and nominal joints.
Enter your values to see the result.
Good to know
Area estimate, not a cutting or bond schedule. Frogs, specials, piers, returns and boundary joints require a separate take-off. Standard example gives 59.259 units/m², often rounded to about 60.
Sources
- BDA dimensions
Estimates are not design approval or British Standards compliance checks. Structural arch, retaining-wall, wind, foundation, lintel and masonry-capacity design are not performed. Use the project engineer’s specification.