UK Brick Dimensions — Standard Sizes Reference
The standard UK brick has remained essentially the same size for over a century. Understanding brick dimensions, coordinating sizes, and the number of bricks per m² is essential for accurate estimating and ordering. This reference page covers everything you need to know.
Standard UK Brick Size
Length
215 mm
Width (depth)
102.5 mm
Height
65 mm
With a standard 10 mm mortar joint, the coordinating size (also called the working size) is 225 × 112.5 × 75 mm. This means one brick plus one mortar joint equals 225 mm long, 112.5 mm deep, and 75 mm high. The coordinating dimension system means bricks module perfectly: four courses of brickwork equal 300 mm in height.
Bricks Per m² by Bond Type
| Bond Type | Wall Thickness (mm) | Bricks per m² | Notes |
|---|---|---|---|
| Stretcher bond (half brick) | 102.5 | 60 | Most common: cavity wall outer leaf, garden walls |
| English bond (one brick) | 215 | 120 | Alternating courses of headers and stretchers |
| Flemish bond (one brick) | 215 | 120 | Headers and stretchers alternating within each course |
| English garden wall | 215 | ~90 | Three stretcher courses to one header course |
| One-and-a-half brick | 327.5 | 180 | Thick structural walls, retaining walls |
All figures assume standard 10 mm mortar joints. Add 5–10% for waste and cuts.
Brick Types and Classifications
| Type | Strength (N/mm²) | Water absorption | Use |
|---|---|---|---|
| Common brick | 20+ | Varies | Internal walls, hidden work |
| Facing brick | 20–60 | Varies | External visible walls, aesthetic purposes |
| Engineering Class A | ≥125 | ≤4.5% | Below DPC, manholes, retaining walls (BS EN 771-1) |
| Engineering Class B | ≥75 | ≤7% | Below DPC, general engineering work (BS EN 771-1) |
Mortar Quantities
For half-brick (stretcher bond) walls, you need approximately 0.02 m³ of mortar per m² of brickwork. For one-brick walls (English or Flemish bond), this doubles to around 0.04 m³ per m². A standard mortar mix for above-DPC brickwork is 1:5 or 1:6 (cement:sand). Below DPC, use a stronger 1:3 mix or add a waterproofer.
Calculate Your Brick Quantities
Use our free calculators for accurate brick and mortar estimates:
- Brick Calculator — calculate bricks needed for walls, piers and features
- Mortar Calculator — sand and cement quantities for bricklaying
- Lintel Sizing Calculator — correct lintel for your opening
Brick dimensions conform to BS EN 771-1. Actual sizes may vary slightly between manufacturers. Imperial bricks (from older buildings) are typically 9″ × 4.5″ × 3″ (229 × 114 × 76 mm) and are slightly larger than modern metric bricks.