Brick Calculator

Learn more: brick calculations and bricklaying

How many bricks per square metre

The number of bricks required depends on brick format and bond pattern. For UK standard bricks (215x65mm) in stretcher bond with 10mm mortar joints, approximately 60 bricks per square metre are needed. In English bond (a two-leaf pattern), approximately 120 bricks per square metre are needed. US modular bricks in running bond require approximately 72 bricks per square metre. The calculator adjusts automatically for your chosen format and bond pattern.

Mortar volume and cement bag count

Approximately 25-30 litres of fresh mortar are needed per square metre of single-skin stretcher bond brickwork. A standard 3:1 sand:cement mix requires about 8kg of cement and 32kg of sand per 10 litre bucket of mortar. Always add 10-15% waste allowance to your mortar quantities. The calculator shows cement and sand bags required at the 3:1 mix ratio, accounting for your wall area, bond pattern, and waste factor.

English bond vs stretcher bond

Stretcher bond shows the long side of every brick on the face - it is the most common single-skin brickwork pattern. English bond alternates courses of stretchers (long side out) with courses of headers (short side out), creating a stronger double-skin wall. English bond uses approximately twice as many bricks per face area as stretcher bond but produces a much stronger wall suitable for structural or load-bearing applications.

Deducting windows and doors

Enter the total wall area, then deduct the area of windows and doors in square metres. The calculator subtracts this from your total and gives you the net area to be bricked. Under-ordering bricks means a second delivery from a different batch that may not colour-match. Over-ordering wastes expensive materials. Accurate deductions prevent both mistakes.

Why Flemish bond needs more cut bricks without needing more bricks overall

Flemish bond alternates a header and a stretcher in every course across the whole face, but like stretcher bond it is typically laid as a single skin, so its bricks-per-square-metre count works out about the same as stretcher bond. The calculator reflects this: Flemish and stretcher bond use the same brick count factor for a given wall area.

Where Flemish bond costs more is at wall ends and corners. Keeping the header-stretcher alternation correct right up to a return or opening needs extra cut bricks, usually queen closers, that a straightforward stretcher bond does not require. That waste shows up as cut-brick count on site, not as a change to the overall bricks-per-square-metre figure.

A worked example: bags needed for a 10 m2 wall

For a 10 m2 wall in stretcher bond with 10mm joints, mortar volume works out to about 0.25 m3 (10 m2 x 0.025 m3 per m2). At roughly 350kg of cement and 1,350kg of sand per cubic metre of mortar, that is about 87.5kg of cement and 337.5kg of sand.

Rounded up to full 25kg bags, that is 4 bags of cement and 14 bags of sand, before adding a waste allowance. Building the same wall in English bond roughly doubles every one of those numbers, since its double-skin construction uses twice the mortar, cement, and bricks per square metre.

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Last reviewed: August 20, 2026