Brick Calculator

For modular brick (3.625 x 2.25 x 7.625 inches) with a standard 3/8-inch mortar joint, you need approximately 6.75 bricks per square foot of wall. Standard brick (3.5 x 2.25 x 8 inches) works out to about 6.55 per sqft. These numbers assume a single wythe (one brick thick) running bond pattern. Add 5–10% for waste and breakage on most jobs.

Type S mortar is the standard choice for exterior walls, load-bearing walls, and any below-grade application. It has a minimum compressive strength of 1,800 PSI and good flexural bond strength. Type N mortar (750 PSI) is acceptable for above-grade exterior veneer where wind loads are moderate. Never use Type N below grade or on retaining walls. Type M (2,500 PSI) is overkill for most above-grade work but required for some engineered masonry.

Measure the rough opening width and height for each window and door, then multiply to get the square footage. A standard 3-foot by 5-foot window is 15 sqft. A 3-foot by 7-foot door is 21 sqft. Sum all openings and enter that total in the “Openings” field. The calculator subtracts this from total wall area before computing brick count. Keep your waste factor at 10% even after deducting openings, because cuts around openings generate more waste than straight runs.

A 10% waste factor covers most residential and small commercial jobs with standard running bond. Increase to 12–15% for complex patterns (herringbone, basket weave), walls with many openings, or if the brick supplier’s quality control is inconsistent (higher chip rate). For salvage or reclaimed brick, go 15–20% because rejection rates are higher. Always order all brick from the same lot to avoid color variation.