Brick calculator (how many per wall)
Calculate how many bricks or blocks you need from the wall area and brick size, including waste.
The face is the visible side of the brick (e.g., ~19 × 9 cm). Includes the mortar joint and waste.
How the calculation works
Each brick occupies its face area plus the joint: (length+joint) × (height+joint). Dividing 1 m² by that gives bricks per m². Multiply by the wall area and add waste.
Examples
- A 19×9 cm brick with 1 cm joint: ~50 per m² → a 20 m² wall uses ~1,100 (with waste).
- Larger block (39×19 cm): ~12.5 per m² — far fewer pieces.
Frequently asked questions
How much waste should I add?
About 10% for breakage and cuts; more for walls with many openings.
Does the mortar joint count?
Yes — each brick takes its face plus the joint (~1 cm). Ignoring it overbuys bricks.
Should I subtract doors and windows?
Yes, to avoid overbuying. Compute the openings' area and subtract from the wall total.
Should the mortar joint be included?
Yes. Each brick occupies its own size plus the joint — ignoring it overestimates quantity by about 10%.
How much waste should I allow?
5–8% for simple walls, 10% with many cuts, up to 15% for exposed brickwork.
How do I know if a wall is structural?
You often cannot tell by looking, and demolishing a structural wall is among the most dangerous renovation mistakes.
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Updated on June 30, 2026 · by Rafael Rossi · Methodology & sources