How many bricks does a house need?
To answer the question bricks for a house, the answer depends on wall area, not floor area: bricks go into the walls, not the floor. The correct formula is: perimeter × wall height − openings = wall area, then wall area × bricks/m² × 1.1 (including 10% reserve). Below, we work through a 100 m² detached house step by step, using both Porotherm 30 N+F and B30 bricks.
For an accurate wall-by-wall calculation, use the free calculator:
Start house calculation →The right approach: wall area, not floor area
Two houses with the same floor area can need very different quantities: an elongated layout has a larger perimeter than a square one, and wall height and openings differ. Always begin with wall area, in four steps:
- Perimeter × wall height = gross external wall area
- − opening area (doors, windows) = net wall area
- × pcs/m² for the selected product = brick quantity
- × 1,1 (10% reserve for cutting and breakage) = quantity to order
Per-m² requirements vary greatly: Porotherm 30 N+F needs 16, B30 35–36 and solid bricks in a 25 cm wall 102–104. Find values by type in the bricks per square metre guide; find dimensions in the brick dimension table guide.
Example: 100 m² single-storey house
Take a single-storey 10×10 m house with 2.7 m wall height, the common 100 m² example:
- Perimeter: 4 × 10 = 40 m
- Gross external wall area: 40 × 2.7 = 108 m²
- Openings (entrance, patio door, windows): about −15 m²
- Net wall area: ~93 m²
A) Porotherm 30 N+F (16 pcs/m², 80 pcs/pallet)
- Quantity: 93 × 16 = 1 488 pcs
- With 10% reserve: 1,488 × 1.1 ≈ 1 637 pcs
- Pallet requirement: 1,637 / 80 = 21 pallets
B) B30 block brick (35 pcs/m², 196 pcs/pallet – Bakonytherm)
- Quantity: 93 × 35 = 3 255 pcs
- With 10% reserve: 3,255 × 1.1 ≈ 3 581 pcs
- Pallet requirement: 3,581 / 196 = 19 pallets
B30 needs more than twice as many units, but its larger pallet capacity (196) makes the pallet quantity similar. Compare total material costs for both options using the Porotherm and the B30 preset calculator for comparison.
Additional quantity: partitions
The calculation above covers only external load-bearing walls. Internal partitions typically use Porotherm 10 N+F partition bricks, with dimensions 100×500×238 mm, which gives 8 units per square metre, with 96 units per pallet. For example, 30 m² of partitions require 30 × 8 = 240 units, or with 10% reserve 264 pcs, meaning 3 pallets. Add this quantity in the partition preset calculator calculates it for your own layout.
Overview: brick requirements for 80–150 m² houses
The values below rough estimates rounded estimates for single-storey, roughly square houses with 2.7 m walls, proportionate opening deductions and 10% reserve:
| Floor area | Net wall area (estimate) | Porotherm 30 N+F (16 pcs/m²) | B30 (35 pcs/m²) |
|---|---|---|---|
| 80 m² | ~85 m² | ~1 500 pcs (19 pallets) | ~3 250 pcs (17 pallets) |
| 100 m² | ~93 m² | ~1 650 pcs (21 pallets) | ~3 600 pcs (19 pallets) |
| 120 m² | ~100 m² | ~1 750 pcs (22 pallets) | ~3 850 pcs (20 pallets) |
| 150 m² | ~110 m² | ~1 950 pcs (25 pallets) | ~4 250 pcs (22 pallets) |
Rounded values excluding partitions. Multi-storey houses, lofts or complex layouts can differ considerably. Measure each wall for accurate quantities using the Calculator.
Frequently asked questions
How many bricks for a 100-square-metre house?
For a typical 100 m² single-storey house (40 m perimeter, 2.7 m wall height, 15 m² openings), external walls need about 1,637 Porotherm 30 N+F units (21 pallets) or 3,581 B30 bricks (19 pallets), including 10% reserve and excluding partitions. Actual quantities depend on measured wall areas.
Why isn't floor area enough for brick calculations?
Bricks go into the walls, not the floor. Two equally sized houses may have very different perimeters, heights and openings. Calculate perimeter × height − openings = wall area, then wall area × bricks/m² × 1.1.
How many bricks for a garage or fence?
Use the same method: wall area × bricks/m² × 1.1. A 3×6 m garage with 2.5 m walls has an 18 m perimeter and 45 m² gross wall area. After its doors, about 38 m² remains, which with B30 needs (35 pcs/m²) needs about 1,460 bricks including 10% reserve. For a fence, start with length × height; find the per-m² values in the per-square-metre guide guide.
How much reserve should I allow?
Typically allow 10% reserve for cutting, breakage and damaged units. N+F clay units need more cuts at corners and openings; solid bricks more often suffer transport breakage. Later small top-up orders may have disproportionately high delivery costs.
Related guides
Want to plan the wall layout too?
The 3D wall and room planner position walls, doors and windows, then calculate quantities using the same dimensions. You can also edit your plan on a separate page in a larger view.