Key takeaways
- Add a 10 mm mortar joint to each brick dimension before counting.
- Modular brick + joint = 200 × 100 × 100 mm → ~500 bricks per m³.
- Bricks = wall volume ÷ (one brick-plus-joint volume), then add ~5–10% wastage.
- Mortar volume ≈ wall volume − total bare-brick volume; cement comes from the mix ratio.
The quick answer
To count bricks, work in the volume each brick takes up including its mortar joints. Add 10 mm to the brick's length, height and width, multiply those to get the "laid" volume of one brick, then divide the wall's volume by it. For the modular brick the laid size is 200 × 100 × 100 mm = 0.002 m³, so 1 ÷ 0.002 = ~500 bricks per cubic metre of brickwork. Finally add about 5–10% for breakage and cutting.
Why the mortar joint matters
A brick is never laid touching its neighbour — there is a mortar bed under it and a vertical perpend joint beside it, usually about 10 mm each. If you size the wall using the bare brick you will badly over-order. Adding 10 mm to each dimension captures the space the brick truly occupies. For a 230 mm brick that joint is only ~4% per dimension, but compounded across three dimensions it changes the count by more than 10%.
Common brick sizes
The brick you specify drives the count, so confirm the local size first. These are the three you will meet across Pakistan.
| Brick | Nominal size | With 10 mm joint | Bricks per m³ |
|---|---|---|---|
| Pakistan standard | 9 × 4.5 × 3 in (228 × 114 × 76 mm) | 238 × 124 × 86 mm | ≈ 394 |
| Modular | 190 × 90 × 90 mm | 200 × 100 × 100 mm | ≈ 500 |
| Traditional | 230 × 110 × 70 mm | 240 × 120 × 80 mm | ≈ 434 |
A worked example: a 9-inch wall
Take a wall 6 m long, 3 m high and 0.23 m thick (a full-brick "9-inch" wall), built with modular bricks. Wall volume = 6 × 3 × 0.23 = 4.14 m³. At 500 bricks per m³ that is 4.14 × 500 = 2,070 bricks before wastage; adding 8% gives 2,070 × 1.08 ≈ 2,236 bricks to order.
Mortar: the bare bricks take 2,070 × (0.19 × 0.09 × 0.09) = 2,070 × 0.001539 = 3.19 m³, so the mortar (wet) is roughly 4.14 − 3.19 = 0.95 m³. Apply the 1.33 dry-volume factor for mortar (0.95 × 1.33 = 1.26 m³) and split by the mix — at 1:6 that is about 5 bags of cement and 1.1 m³ of sand. The brick calculator does all of this for any wall and brick size, including the mortar and cement.
Then plaster both faces
A finished wall is usually plastered on one or both sides. Once you know the wall area, the plaster calculator works out the cement and sand for the plaster coat at your chosen thickness and mix — the natural next step after the bricks are sorted.
Frequently asked questions
How many bricks are in one cubic metre of brickwork?
With the modular brick (190×90×90 mm) plus a 10 mm joint, each laid brick is 200×100×100 mm, so about 500 bricks fill one m³.
Why add a 10 mm mortar joint to the brick size?
Bricks are laid with a ~10 mm mortar bed and perpend joint, so each brick actually occupies the brick size plus that joint. Adding 10 mm per dimension prevents over-ordering.
What size brick is used in Pakistan?
Pakistan commonly uses 9×4.5×3 in (≈228×114×76 mm); a 190×90×90 mm modular brick and a traditional 230×110×70 mm size are also used.
Sources: the 10 mm joint convention and the 190 × 90 × 90 mm modular brick follow standard trade practice for burnt-clay building bricks and brickwork; the ~500 bricks/m³ figure derives directly from the 200 × 100 × 100 mm laid module. Mortar dry-volume factor (≈1.33) and mix ratios per standard masonry references. Pakistani 9 × 4.5 × 3 in brick is the common kiln size.
Last reviewed 2026-06-14