Brick Calculator

A brick does not take up the area of its face. It takes up its face plus one mortar joint in each direction, because every brick shares half a joint with each neighbor. That combined dimension is the module, and the module is what tiles the wall. The math is bricks per sq ft = 144 ÷ [(length + joint) × (height + joint)], with everything in inches and 144 being the square inches in a square foot. A modular brick of 7-5/8 by 2-1/4 in with a 3/8 in joint gives about 6.9 bricks per square foot — the source of the familiar "seven bricks per square foot" rule of thumb, which is a rounding of this specific case rather than a universal constant. The joint is not a rounding detail. Widen it from 3/8 to 1/2 in and the module grows in both directions, dropping the count by several percent across the wall. Narrow it and the count rises. If you are matching an existing wall, measure its joints rather than assuming — older masonry frequently used wider joints than modern practice.

Brick sizes are quoted two ways, and confusing them is the fastest route to a wrong order. The nominal size is the module — the brick plus its intended joint, expressed in round numbers so masons can lay out openings and courses in whole inches. The actual size, sometimes called the specified size, is the fired brick you can put a tape on, and it is smaller. The difference is the joint the brick was designed for. This is the same convention that makes a 2 by 4 not measure two inches by four, and it means a brick advertised in round numbers will never measure those numbers. Enter the actual face dimensions here and let the calculator add the joint. If you enter nominal dimensions and a joint, you have counted the joint twice and will come up short. And "brick" is not one size. Modular, standard, queen, king, engineer, Norman, utility and jumbo are all real product names covering meaningfully different faces, and dimensions vary between manufacturers even under the same name. A larger-face brick covers more wall per unit, so the count can differ by a third or more between two products that both look like bricks on a pallet. Pull the spec sheet for the exact product, or measure a sample, before you order anything.

The calculator counts the bricks facing you. How many layers of brick the wall is made of is a separate question, and it is the one that doubles a bill. A single layer of brick is a wythe. Most brick on modern American houses is a single-wythe veneer: a non-load-bearing skin standing on the foundation ledge in front of a wood or steel frame wall, tied back with corrugated metal ties. It carries its own weight and nothing else. A two-wythe or structural wall needs roughly twice the brick for the same elevation, plus whatever ties the wythes together. Brick veneer is also a drainage assembly, not a waterproof one. Brick and mortar absorb water, so the design depends on an air cavity behind the brick, flashing, and weep holes at the base of the wall to let water back out. Blocking the weeps, filling the cavity, or leaving the flashing out traps moisture against the sheathing, and that is a mold and rot problem rather than a masonry one. Details like these are why the assembly matters more than the brick count. Anything structural — a load-bearing masonry wall, a retaining wall, a chimney, the lintel that carries brick over a window or door opening, and the foundation supporting any of it — is designed by a licensed engineer or built to a design that satisfies your local building code. Masonry is heavy, and the failure modes are not gentle. This page estimates quantities to buy, not whether the wall stands up.

Bricks are the count everyone asks about and roughly half the material list. Mortar fills the bed joints under each course and the head joints between bricks. How far a bag goes depends on the joint width, the brick size, how much the brick absorbs, and how much falls off the trowel, and the spread between a tight 1/4 in joint and a generous 1/2 in joint is large. Use the coverage figure from the mortar manufacturer for the joint size you are actually laying, and mix mortar type to what the application and your code require — mortar types differ in strength and are not interchangeable. The rest of the order for a veneer typically includes wall ties, flashing, weep vents, through-wall membrane, reinforcement where specified, and sand and mixing water if you are not using a premixed product. Steel lintels span the openings. On packaging: brick is sold by the cube or pallet, and the count per cube varies by manufacturer and brick size — it is rarely a round number, and it is rarely the number you calculated. Ask what the cube count is before ordering so you know whether you are buying two cubes or two cubes plus a loose strap.

Plan on an overage allowance for the same reasons as any other masonry material. Cut bricks at openings, corners, rakes and returns leave offcuts that often cannot be reused. Breakage happens in delivery, in handling, and on the saw. And a small stack of spares in the garage is what makes a future repair — a cracked brick, a section rebuilt after a leak — invisible instead of obvious. Common practice on straightforward walls is a modest allowance in the range of a few percent up to about 10%, with walls full of openings, corners and cut angles at the higher end. Patterns other than a plain running bond, and any layout involving angled or soldier courses, consume more. The stronger argument for buying everything at once is color. Brick color comes from clay chemistry and the position of each brick in the kiln, so it varies within a run and more so between runs. Manufacturers handle this by blending, and so should you: pull bricks from several cubes at a time as you lay rather than emptying one cube before opening the next. Working straight through one pallet at a time produces horizontal bands of color across the wall, which is permanent and very hard to look past. Buying a second delivery months later, from a later production run, is worse still. One safety point. Cutting brick, block and mortar releases respirable crystalline silica, a recognized lung hazard. Wet-cut where possible, work outdoors, and use appropriate respiratory protection — a masonry saw run dry produces a great deal of it.