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.

Gable ends and other walls that are not rectangles

The calculator wants a length and a height, which quietly assumes a rectangle. A gable end is a rectangle with a triangle sitting on top, so you work out the two pieces separately and add them. Picture a gable wall 24 ft wide with 8 ft of wall up to the eaves, and a peak rising another 6 ft above that line. The rectangle is 24 x 8 = 192 sq ft. The triangle is half of base times height, 0.5 x 24 x 6 = 72 sq ft. The total face is 264 sq ft.

At 7 bricks per square foot that is 1,848 bricks, and with 10 percent waste it is 2,033 once rounded up. To feed 264 sq ft into a tool that only takes two numbers, keep the 24 ft length and enter an equivalent height of 264 / 24 = 11 ft. The same wall in metric, 6 m wide with 2.4 m to the eaves and a 1.5 m peak, is 14.4 + 4.5 = 18.9 square meters. At 60 per square meter that is 1,134 bricks, or 1,248 with 10 percent waste.

Sloping edges are the awkward part. Every course along a rake has to be cut to the pitch, and each cut leaves an offcut that is rarely usable. On a wall like this, a waste figure of 12 to 15 percent is more realistic than 10. At 15 percent the 264 sq ft gable above needs 2,126 bricks instead of 2,033, a difference of 93 that you would rather own than be short.

Adding up several walls: a perimeter example

Garden beds, a shed base, a barbecue surround, and a small room addition all involve more than one wall. Measure each wall's face area, subtract openings, add the results, and apply the waste factor once to the grand total. Applying it to each wall separately gives nearly the same answer but invites rounding drift.

Take a low brick base around a 14 ft by 10 ft shed, 3 ft high. The perimeter is 2 x (14 + 10) = 48 ft, so the face is 48 x 3 = 144 sq ft. That is 144 x 7 = 1,008 bricks, and 1,109 with 10 percent waste. If the base has a 3 ft wide gap for the door, subtract 3 x 3 = 9 sq ft and the net face is 135 sq ft. That gives 945 bricks before waste and 1,040 after.

Measuring the full outside length of each wall counts the corner bricks twice, once for each wall that meets there. For a single-wythe wall the overlap is only a few inches per corner, which the waste factor swallows without trouble. You only need to correct for it on very short walls with many corners, where the overlap becomes a noticeable fraction of the total.

Cross-checking with courses and bond

A course is one horizontal row of bricks. Counting courses gives you a second route to the same answer and exposes dimension problems before the mason does. A modular brick with its joint occupies 8 in along the wall and 2 2/3 in up the wall, so three courses stack to exactly 8 in. An 8 ft wall is 96 in tall and holds 36 courses. A 7 ft wall is 84 in, which is 31.5 courses and ends mid-brick; adding 4 in to reach 88 in gives a clean 33 courses.

Length works the same way. A 24 ft wall is 288 in, which is exactly 36 bricks per course. A 25 ft wall is 300 in, or 37.5 bricks per course, which means a half brick at one end in every other course, whether you cut it or buy it. Choosing wall lengths in multiples of 8 in, or at least 4 in, saves cutting.

Now compare the hand count for the 24 ft by 8 ft wall: 36 bricks per course times 36 courses is 1,296 bricks. The area method with the default rate gives 192 x 7 = 1,344, about 3.7 percent higher, because 7 is a rounded-up version of 6.75. With 10 percent waste on top, you would order 1,479 from the calculator against 1,426 from the exact count. The gap is your safety margin, and it is why a dimensionally tidy wall can often use a lower waste figure than a wall that needs cutting everywhere.

When your brick is not the modular size

The 7 per square foot default belongs to the modular brick. Other common shapes cover very different amounts of wall, so the rate must change. Commonly listed nominal face sizes, with the joint included, give these approximate coverages: a Roman brick at 12 x 2 in covers 24 sq in, or 6 per square foot; a Norman brick at 12 x 2 2/3 in covers 32 sq in, or 4.5 per square foot; and a utility brick at 12 x 4 in covers 48 sq in, or 3 per square foot. Real products vary by manufacturer, so treat these as starting points and prefer the coverage figure on the supplier's data sheet.

The effect on the order is large. Using the 167 sq ft net wall from the main guide with 10 percent waste, a Norman brick at 4.5 per square foot needs 827, a utility brick at 3 per square foot needs 552, and a Roman brick at 6 per square foot needs 1,103. The default modular rate of 7 gives 1,286 for the same wall.

The calculator's bricks-per-square-foot field accepts values from 3 to 15, so all of these fit. Your own rate is the area of one square foot, 144 sq in, divided by the face area of one brick plus joint in square inches. For metric work, divide 1,000,000 sq mm by the face area in sq mm. Always add the joint to the brick's face dimensions before dividing, or you will undercount.

From brick count to delivery: weight, cubes, and footings

A count of bricks is not yet an order. Suppliers usually sell by the thousand, or in packs that go by names such as cubes or pallets, and the quantity per pack varies with the product. Suppose a pack holds 500. Your 1,286 bricks then becomes three packs, or 1,500 bricks, leaving about 214 spare. Round up to full packs, then confirm with the supplier that the packs come from a single production lot.

Weight matters for delivery and for what the wall sits on. A modular clay brick commonly weighs somewhere in the range of 4 to 5 pounds, but hollow, cored, and concrete units differ, so check the product sheet. At roughly 4.5 pounds each, 1,286 bricks come to about 5,800 pounds, close to three US tons. That affects where the truck can unload, whether you can move it by hand, and how many trips a wheelbarrow takes.

The same weight is why a brick wall needs a proper footing. Footing width and depth depend on soil, frost depth, wall height, and local code, and a freestanding wall also has to resist wind. For anything beyond a low garden border, a local mason or the building department will tell you what the footing must be.