How Many Bricks in 1 Cubic Metre of Brickwork?

One cubic metre of brickwork needs 500 modular bricks (190 × 90 × 90 mm) or roughly 390 to 435 traditional bricks, depending on the exact size, when the mortar joints are 10 mm thick. That count is before wastage. The mortar takes up about 0.22 to 0.23 m³ of each cubic metre (wet volume). In a 1:6 mix that comes to about 1.2 to 1.3 bags of cement and 0.25 to 0.26 m³ of sand.

For walls it is easier to count per square metre of face. With 230 × 115 × 75 mm bricks, a 115 mm wall needs about 49 bricks/m² and a 230 mm wall about 96 bricks/m². Add about 5% for breakage and cutting.

Why the count depends on brick size

Bricks are counted using their nominal size, which is the actual size plus one 10 mm joint in each direction. Divide 1 m³ by the nominal volume of one brick and you get the number of bricks. Bricks from country kilns vary from lot to lot. Before estimating, measure ten bricks from the actual delivery and use the average size.

Step by step: bricks and mortar in 1 m³ (modular bricks)

1. Nominal volume of one brick = 0.20 × 0.10 × 0.10 = 0.002 m³
2. Number of bricks = 1 ÷ 0.002 = 500 bricks
3. Volume of the bricks alone (actual size) = 500 × 0.19 × 0.09 × 0.09 = 0.7695 m³
4. Wet mortar = 1 − 0.7695 = 0.2305 m³
5. Dry volume of mortar = 0.2305 × 1.33 = 0.3066 m³
6. Cement (1:6, so 1 part in 7) = 0.3066 ÷ 7 = 0.0438 m³ × 1440 kg/m³ = 63 kg ≈ 1.26 bags
7. Sand = 0.3066 × 6/7 = 0.263 m³ ≈ 9.3 cft

The table gives quantities per 1 m³ of brickwork in 1:6 cement mortar, using a dry factor of 1.33 and no frog filling.

Bricks per m² for 115 mm and 230 mm walls

Most site work is measured in square metres of wall, so the face method is more practical. The figures below use the common 230 × 115 × 75 mm brick (nominal 240 × 125 × 85 mm).

115 mm (half-brick) wall

Each brick shows its 230 × 75 mm face. With joints, one brick covers 0.240 × 0.085 = 0.0204 m² of wall, so the count is 1 ÷ 0.0204 = 49 bricks per m². The wet mortar works out to about 0.0178 m³ per m².

230 mm (one-brick) wall

In English bond the courses alternate. A header course needs 1 ÷ (0.125 × 0.085) = 94.1 bricks/m². A stretcher course has two leaves and needs 2 ÷ (0.240 × 0.085) = 98.0 bricks/m². The average is about 96 bricks per m², and the wet mortar is about 0.039 m³ per m².

You might expect 0.23 m³ × 392 = 90 bricks per m². The real figure is higher because the per-m³ count assumes a joint on every face. In a 230 mm wall, the headers run through the full wall thickness with no joint across it. For walls, use the per-m² figures.

Worked example: a 230 mm wall with a door

The wall is 5.0 m long and 3.0 m high, built in 230 mm brickwork with 230 × 115 × 75 mm bricks in 1:6 cement mortar. It has one door opening of 1.0 × 2.1 m.

1. Gross area = 5.0 × 3.0 = 15.0 m²
2. Less the door: 1.0 × 2.1 = 2.1 m², so the net area = 15.0 − 2.1 = 12.9 m²
3. Bricks = 12.9 × 96 = 1238
4. Add 5% wastage: 1238 × 1.05 = 1300, so order 1300 bricks
5. Wet mortar = 12.9 × 0.0394 = 0.508 m³
6. Dry volume = 0.508 × 1.33 = 0.676 m³
7. Cement = 0.676 ÷ 7 = 0.0966 m³ × 1440 = 139 kg = 2.8 bags, so buy 3 bags
8. Sand = 0.676 × 6/7 = 0.579 m³ ≈ 20.5 cft

As a check, the wall volume is 12.9 × 0.23 = 2.97 m³, and 1238 ÷ 2.97 gives about 417 bricks per m³. That is in the expected range for this size of brick in a one-brick wall. If an RCC lintel or beam runs through the wall, deduct its volume as well before counting bricks. To work out a full house or compound wall in one go, try the Nirmaan house estimator or the boundary wall estimator.

Bricks per cubic foot

Some contractors still quote brickwork per cft. One cft is 0.0283 m³, so it takes about 14 modular bricks or about 11 traditional 230 × 115 × 75 mm bricks, before wastage.

Common mistakes

• Using 500 for every brick. The figure of 500 per m³ holds only for 190 × 90 × 90 mm modular bricks. Local bricks are bigger, so fewer are needed per m³, but each one uses more mortar.
• Ordering sand on wet volume. If you skip the dry factor, the order falls about 25% short.
• Too little wastage. Allow about 3–5% for good machine-made or wire-cut bricks and 5–10% for country bricks with broken edges. These are thumb rules, so adjust them to the quality of the lot.
• Not deducting concrete members. In framed buildings, deduct columns, beams, lintels and sills from the wall area.
• Ignoring the frog. Laying frogs upward and filling them adds mortar, so budget toward 0.25–0.30 m³ of wet mortar per m³.
• Laying dry bricks. Soak clay bricks before use so they do not suck water out of the mortar. See types of bricks for how different bricks behave.