Brick Calculator (UK)
Last updated: 12 August 2026
Work out how many bricks you need for your wall, based on the standard UK brick size (215 × 102.5 × 65mm) with a 10mm mortar joint. Includes a wastage allowance and an estimate of mortar bags.
How the calculation works
A standard UK brick measures 215mm long × 65mm high. With a 10mm mortar joint, each brick occupies 225mm × 75mm of wall face — that is 0.016875 m² per brick, or roughly 60 bricks per square metre in a half-brick wall. A one-brick-thick wall doubles this to around 120 per square metre.
We multiply your wall area (minus openings) by the bricks-per-m² figure, then add your chosen wastage allowance for cuts and breakages.
Bricks per square metre at a glance
| Wall type | Bricks per m² | Example: 10 m² wall |
|---|---|---|
| Half brick (102.5mm, single skin) | 60 | 600 bricks |
| One brick (215mm, double skin) | 120 | 1,200 bricks |
| Brick slips / feature course | 60 per face | 600 slips |
A standard pack of UK bricks holds around 400–500 bricks depending on manufacturer, so a 10 m² single-skin wall is roughly one and a half packs.
Frequently asked questions
How many bricks are in 1 square metre?
Approximately 60 bricks per m² for a half-brick (single skin) wall using standard UK bricks with 10mm joints, or 120 per m² for a one-brick wall.
How many bricks are in a pack?
Most UK brick packs contain 400 to 500 bricks, though it varies by manufacturer — Ibstock and Wienerberger packs are commonly 400 or 500. Check the pack quantity before ordering so you are not caught short by a half pack.
How much wastage should I allow?
Allow 5 to 10% extra for cuts and breakages. Go to 15% for walls with lots of openings, piers or decorative cuts, and order from one batch to avoid colour variation.
How much mortar do I need per 100 bricks?
Allow roughly three 25kg bags of ready-mixed mortar per 100 bricks. If mixing your own, a 1:4 cement to soft sand mix is typical for general brickwork.
How many bricks do I need for a 6-metre garden wall?
A 6m long by 1.8m high half-brick wall is 10.8 square metres, which needs roughly 648 bricks. With a 10% wastage allowance, order about 715 bricks.
What size is a standard UK brick?
The standard UK brick is 215mm long, 102.5mm wide and 65mm high. With a 10mm mortar joint it occupies 225mm by 75mm of wall face, which is why around 60 bricks fill one square metre of a single-skin wall.
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Slab and footing volumes in m³, with bag counts or ballast & cement.
Estimates are for guidance only. Material dimensions, densities and coverage vary by supplier — always confirm quantities before ordering, and consult a qualified professional for structural work.