Metric Unit Calculator
The formula, your substituted values, and the evaluated result are shown below.
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View offerAffiliate link — we may earn a commission at no extra cost to you.Estimate the number of brick units needed from area, unit coverage, and waste allowance.
This is a planning estimate. Confirm dimensions, allowances, material specifications, applicable codes, and supplier requirements before purchasing or construction.
Estimate the number of brick units needed from area, unit coverage, and waste allowance.
The calculator divides the wall area by the face area one brick covers (including its mortar joint), adds a waste allowance, and rounds up to a whole brick:
Bricks = round up( wall area (m²) ÷ coverage per brick (m²) × (1 + waste % ÷ 100) )
The key input is the coverage per brick. Work it out from the brick's length and height plus one mortar joint (usually 10 mm) on each:
Coverage = (length + 0.01) × (height + 0.01), in metres
| Brick | Size (L × H × W) | Coverage incl. 10 mm joint | Bricks per m² |
|---|---|---|---|
| Australian standard | 230 × 76 × 110 mm | 0.0206 m² | ≈ 48.5 |
| Australian double-height | 230 × 162 × 110 mm | 0.0413 m² | ≈ 24 |
| UK standard | 215 × 65 × 102.5 mm | 0.0169 m² | ≈ 59 |
| US modular | 7⅝ × 2¼ × 3⅝ in | ≈ 0.0137 m² | ≈ 73 (about 6.75 per ft²) |
Bricks are sold in packs (often around 400–500 per pack, depending on the brick), so you'd round up to whole packs. For a double-brick or cavity wall with two skins, double the count.
Allow 5% for plain walls with few cuts. Allow 10% for walls with lots of corners, piers, openings or decorative bonds, or when using second-hand bricks, which have more culls.
As a rough guide, allow about 0.02 m³ of mortar per square metre of single-skin wall with standard bricks, or roughly one 20 kg bag of premixed mortar for every 25–30 bricks. Check the yield on your product.
About 48–50 Australian standard bricks, 59–60 UK bricks, or around 73 US modular bricks (about 6.75 per ft²), each with a 10 mm joint.
Retaining walls, tall freestanding walls and anything load-bearing should be designed and approved to your local code. Many councils also regulate front fences and boundary walls above a set height.
An experienced bricklayer might lay roughly 300–500 standard bricks a day on straightforward work, so 1,000 bricks is typically two to three days for one bricklayer.