How many bricks do I need for a wall?

Start with the area of the wall face

Bricks are counted by how much wall face they cover, so everything starts with area. For a plain rectangular wall, multiply the length by the height, both in the same unit. A wall 25 ft long and 8 ft high has a face area of 200 square feet. In metric, a wall 5 m long and 2 m high is 10 square meters.

The Brick Calculator then multiplies that area by a coverage rate: bricks per square foot in US mode, or bricks per square meter in metric mode. The defaults are 7 per square foot and 60 per square meter. Those two defaults describe the same kind of wall, just in different units, so you will get a consistent answer whichever system you use.

The formula

Bricks = wall area x bricks per unit area x (1 + waste percentage / 100), rounded up to a whole brick.

Rounding up is deliberate, because you cannot buy a fraction of a brick. A calculated 1,285.9 becomes 1,286. The waste percentage defaults to 10 percent in the calculator, and you can change it from 0 to 30 percent.

Everything else in this guide is about getting the three inputs right: the true wall area, the true coverage rate for your brick and joint, and a waste figure that matches the difficulty of the job.

Worked example: a simple wall

A solid wall 25 ft long and 8 ft high has an area of 25 x 8 = 200 sq ft. At 7 bricks per square foot, that is 200 x 7 = 1,400 bricks before waste. With 10 percent waste, 1,400 x 1.10 = 1,540 bricks.

In metric, a 5 m by 2 m wall is 10 square meters. At 60 bricks per square meter that is 600 bricks, and 600 x 1.10 = 660 bricks with 10 percent waste.

A smaller job: a garden wall 20 ft long and 6 ft high is 120 sq ft, which gives 120 x 7 = 840 bricks, or 924 with 10 percent waste.

• Area: 25 x 8 = 200 sq ft
• Before waste: 200 x 7 = 1,400 bricks
• With 10 percent waste: 1,400 x 1.10 = 1,540 bricks
• Metric: 5 x 2 = 10 sq m, 10 x 60 = 600, with waste 660 bricks
• Garden wall: 20 x 6 = 120 sq ft, 120 x 7 = 840, with waste 924 bricks

Subtract the openings

The calculator does not know where your doors and windows are. It takes the length and height you type and treats the whole rectangle as brick. If the wall has openings, subtract their area yourself and enter the net figure, or you will over-order.

Take the 25 ft by 8 ft wall again, and put in a door 3 ft wide and 7 ft tall (21 sq ft) and one window 3 ft by 4 ft (12 sq ft). The openings total 33 sq ft, so the net brick area is 200 - 33 = 167 sq ft. At 7 per square foot that is 1,169 bricks, and with 10 percent waste it is 1,286. Without subtracting the openings you would have ordered 1,540, which is 254 bricks too many.

The calculator takes only a length and a height, so to enter 167 sq ft you can keep the 25 ft length and use an equivalent height of 167 / 25 = 6.68 ft. Another option is to compute the count by hand with the formula above, which is just area times 7 times 1.10. Metric works the same way: a 5 m by 2.4 m wall is 12 square meters, a door 0.9 m by 2.0 m is 1.8 square meters, so the net is 10.2 square meters, or 612 bricks, which is 674 with 10 percent waste.

• Gross wall: 25 x 8 = 200 sq ft
• Door: 3 x 7 = 21 sq ft; window: 3 x 4 = 12 sq ft; openings = 33 sq ft
• Net area: 200 - 33 = 167 sq ft
• Bricks: 167 x 7 = 1,169; with 10 percent waste, 1,286
• Skipping the subtraction orders 254 bricks too many

Single wythe versus double wythe

A wythe is one vertical layer of brick, one brick thick. The default coverage rate assumes a single-wythe wall, where you see one brick of depth. A freestanding garden wall, a veneer over a framed wall, or a low planter is usually that.

A double-wythe wall has two layers, so it needs about twice as many bricks for the same face area. Using the net 167 sq ft from above: single wythe is 1,169 bricks before waste, and double wythe is 2,338. With 10 percent waste, the double-wythe wall is 2,572 bricks against 1,286 for the single.

The Brick Calculator has no thickness setting, but its bricks-per-square-foot field accepts values up to 15, so for a plain double-wythe wall you can enter 14 instead of 7. In metric mode, enter 120 instead of 60. Walls with header courses, cavities, or different bond patterns use bricks differently again, so for anything structural talk to your mason about the real count.

Choosing a waste factor

Waste covers bricks that are cut, chipped, delivered broken, or simply miscounted. The calculator defaults to 10 percent, which is a sensible middle for a plain wall. A simple straight wall with few cuts can sit lower, while a wall with many openings, curves, corners, or a patterned bond that needs lots of cutting should sit higher.

The effect is easy to see on the 167 sq ft net area. With 0 percent waste you need 1,169 bricks. At 5 percent it is 1,228, at 10 percent 1,286, and at 15 percent 1,345. The difference between 5 and 15 percent is 117 bricks, so the choice matters but is not dramatic.

Leftover bricks are not wasted if you keep them. Bricks from different production batches can vary slightly in color, so having extras from the same batch for repairs is useful later. It is also worth ordering all the bricks at once instead of in two trips.

Checking the 7 per square foot number

The default of 7 per square foot is a rounded figure. You can check it from the dimensions of a brick plus its joint. A modular brick presents a face of roughly 8 inches by 2 2/3 inches of wall once the mortar joint is counted, which is 21.33 square inches. A square foot is 144 square inches, and 144 / 21.33 = 6.75 bricks per square foot. So 7 builds in a small cushion of about 4 percent.

In metric, a standard brick 215 mm long and 65 mm high with 10 mm mortar joints covers (215 + 10) x (65 + 10) = 225 x 75 = 16,875 square millimeters. One square meter is 1,000,000 square millimeters, so that is about 59.3 bricks per square meter. The default of 60 is the same idea, rounded up.

Joint width changes everything. Wider joints put fewer bricks in each square foot, and narrower ones put more. If your brick is a different size or you plan wider joints, work out the face area of one brick plus its joint and divide the area of a square foot (or square meter) by it, then type that into the bricks-per-area field.

Mortar is a separate order. How much you need depends on the joint width, the brick size, and how the wall is laid, so get that figure from your supplier or mason instead of guessing from the brick count.

• Modular brick face with joint: about 8 x 2.67 in, 21.33 sq in, 6.75 per sq ft
• Metric brick 215 x 65 mm with 10 mm joints: 225 x 75 mm, about 59.3 per sq m
• Cross-check by courses: a 20 ft wall is 240 in, 240 / 8 = 30 bricks per course
• A 6 ft wall is 72 in tall, 72 / 2.67 = 27 courses, and 30 x 27 = 810 bricks

Common mistakes

These account for most wrong brick counts.

• Forgetting to subtract doors and windows, which inflates the count noticeably on any wall with openings.
• Using the single-wythe rate for a two-layer wall and ending up with half the bricks you need.
• Using nominal brick sizes for coverage when the real brick and joint are different.
• Skipping the waste factor, then running short on the last course.
• Mixing units, such as a length in meters with a height in feet.
• Ordering bricks in two batches that do not match in color.