How UK masonry is measured
UK bricks are 215 × 102.5 × 65mm and blocks are 440 × 215mm on face, both laid with a 10mm mortar joint. That gives a working size of 225 × 75mm for a brick and 450 × 225mm for a block, which is where the familiar figures of about 60 bricks and 10 blocks per square metre come from. The calculators above use these sizes, then add mortar, waste and the 25kg cement bags and bulk bags of sand you buy.
Choosing the right calculator
- Brick calculator: walls in single skin, double skin or cavity construction.
- Block calculator: 100mm, 140mm and 215mm dense or aerated blocks.
- Mortar calculator: sand, cement and lime when you already know the brick or block count.
- Render calculator: sand and cement, monocouche or silicone thin-coat render, plus beads.
- Brick BBQ calculator: a U-shaped garden barbecue with firebricks.
Don't forget the footing
Every wall needs a footing sized for the wall and the ground. For garden walls, use the foundation calculator and read the garden wall guide, which covers footing sizes, coping and when a wall needs piers.