Brick Calculator

How many bricks do I need?

Bricks per sq ft = 144 ÷ ((brick length + joint) × (brick height + joint))
Bricks = (wall area − openings) × bricks per sq ft × wythes × (1 + waste %)

Each brick in a wall covers its face plus one mortar joint along its length and one across its height. With the common 3/8 in joint, a modular brick (7⅝ × 2¼ in face) covers 8 × 2⅝ in, which works out to about 6.9 bricks per square foot of wall face. Brick Industry Association tables, which use modular coursing (three courses to 8 in), list 6.75 modular bricks per square foot; the small difference comes from rounding the course height.

Worked example: a 20 × 4 ft garden wall

• Wall area: 20 × 4 = 80 sq ft.
• Modular brick with 3/8 in joint: 144 ÷ (8 × 2.625) = 6.857 bricks per sq ft, so 80 × 6.857 = 548.6 bricks.
• With 5% waste: 548.6 × 1.05 = 576 bricks for a single wythe.

A free-standing garden wall is normally two wythes thick (or a single wythe with piers), so double the count: about 1,152 bricks. Check local guidance on wall height, footings and reinforcement before building.

Bricks per square foot by size

In the UK and Europe, the standard brick is 215 × 65 mm on face with a 10 mm joint, which gives 60 bricks per square metre for a single skin (half-brick wall).

Mortar

Mortar use depends on joint width, brick size, whether the bricks have cores or frogs, and the bond pattern, so take quantities from the mortar bag or the brick supplier. Mix only what you can use within the working time stated on the bag.

Tips

• Buy all bricks from one batch and mix bricks from several pallets as you lay, so slight colour differences blend in.
• Plan wall dimensions in whole bricks where possible. A modular wall length that is a multiple of 8 in avoids cut bricks at the ends.
• Allow more waste for walls with many corners, piers or decorative patterns.

Step by step: estimating a brick wall

1. Measure the length and height of each wall face.
2. Subtract doors, windows and other openings.
3. Choose the brick size and mortar joint, usually 3/8 in (10 mm).
4. Decide whether the wall is a single veneer or two wythes thick.
5. Add waste and order everything from one batch.

Metric example

A garden wall 5 m long and 1.2 m high has 6 m² of face. With standard 215 × 65 mm bricks and 10 mm joints, that is 6 × 59.3 = 356 bricks per skin, or about 374 with 5% waste. A one-brick-thick wall (two skins) needs twice as many.

Brick bonds and waste

The bond pattern changes how many bricks you cut. A running (stretcher) bond, where each course is offset by half a brick, needs half-bricks only at the ends and corners. Patterns such as Flemish or English bond use headers (bricks laid end-on) that tie two wythes together and change the count per square foot of face, so allow 10% waste and take quantities from the brick supplier's tables for those.

Common mistakes

• Forgetting the mortar joint, which would give 8.4 bricks per square foot for a modular brick instead of about 6.9.
• Counting one wythe for a free-standing wall that needs two.
• Using the nominal size as the actual size. A modular brick is called 8 in but is 7⅝ in long.

Frequently asked questions

Sources

• Brick Industry Association (BIA), Technical Note 10: Dimensioning and Estimating Brick Masonry (brick sizes and quantities per square foot).
• BS EN 771-1 / UK industry practice: 215 × 65 × 102.5 mm brick with 10 mm joints (60 bricks per m² single skin).

Last reviewed 20 October 2026. Results are estimates; see our disclaimer.