How to calculate bricks per square metre (UK standard)
If you are planning an extension, a garden wall, or a garage in the UK, getting your brick quantities right is crucial. Order too few, and your project stalls while you pay a premium for a small second delivery. Order too many, and you've wasted your budget.
Standard UK Brick Dimensions
To calculate how many bricks you need, you first need to know standard sizing. In the UK, a standard metric brick measures:
- Length: 215mm
- Depth: 102.5mm
- Height: 65mm
However, you don't stack bricks dry. You must account for the mortar joint, which is a standard 10mm on all sides. This brings the "working size" of a single brick in a wall to 225mm x 75mm.
The Golden Rule: 60 Bricks per m²
Based on the standard sizes with mortar joints, the mathematical standard used by builders across the UK is:
Single Skin Wall (Half Brick)
You need exactly 60 bricks for every 1 square metre (m²) of wall.
Double Skin Wall (One Brick)
If you are building a cavity wall or a solid 9-inch wall, you double the amount. You need 120 bricks per square metre.
Why do we add 5% for waste?
Our calculator automatically adds 5% to your final total. Why? Because building sites are real-world environments. Bricks get dropped during delivery, some arrive with chipped faces, and your bricklayer will need to cut bricks in half to finish ends, corners, and window reveals. A 5% buffer ensures you don't run out halfway through a course.
Need help with your build in Peterborough?
Calculations are great for planning, but laying bricks perfectly takes years of experience. If you are in Peterborough, Stamford, or Cambridgeshire, let the experts at Advanced-Builders handle it.
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