Brick calculator
A wall 20 ft long and 8 ft high in modular brick takes 1,134 bricks with 5% extra and about 31 bags of 80 lb mortar mix.
Where the numbers come from
The Brick Industry Association's Technical Note 10 lists how many bricks of each size fill 100 sq ft of wall and how much mortar they take, for ⅜ and ½ in joints. Its figures include no waste, so the calculator adds the extra you choose, 5% by default. For mortar, QUIKRETE says an 80 lb bag of its Mortar Mix lays up to 37 standard bricks. The calculator applies that to modular brick and scales it for other sizes by how much more mortar each brick takes in the BIA table.
20 ft × 8 ft = 160 sq ft × 6.75 bricks per sq ft = 1,080 bricks
1,134 bricks ÷ 37 per bag = 31 bags of mortar mix (rounded up)
The BIA also cites the masons' rule of thumb that 8 bags of masonry cement lay 1,000 modular bricks, a rough figure that includes some waste.
Bricks and mortar by size
| Brick | Specified size | Per 100 sq ft | Per sq ft | Mortar, cu ft per 1,000 (⅜ in joint) | Mortar, cu ft per 1,000 (½ in joint) |
|---|---|---|---|---|---|
| Modular | 3⅝ × 2¼ × 7⅝ in | 675 | 6.75 | 8.1 | 10.3 |
| Standard | 3⅝ × 2¼ × 8 in | 655 | 6.55 | 14.5 | 17.8 |
| Queen | 2¾ × 2¾ × 7⅝ in | 550 | 5.5 | 12.2 | 13.5 |
| King | 2¾ × 2⅝ × 9⅝ in | 455 | 4.55 | 14.2 | 16 |
| Engineer modular | 3⅝ × 2¹³⁄₁₆ × 7⅝ in | 563 | 5.63 | 8.5 | 10.8 |
| Closure modular | 3⅝ × 3⅝ × 7⅝ in | 450 | 4.5 | 9.1 | 11.6 |
| Roman | 3⅝ × 1⅝ × 11⅝ in | 600 | 6 | 10.7 | 13.7 |
| Norman | 3⅝ × 2¼ × 11⅝ in | 450 | 4.5 | 11.2 | 14.3 |
| Utility | 3⅝ × 3⅝ × 11⅝ in | 300 | 3 | 12.3 | 15.7 |
Sizes are width × height × length for a ⅜ in joint. Modular brick is the common size in the United States: three courses with their joints make 8 in of height.
Measuring the wall
Multiply the length by the height for each wall and subtract doors and windows. A brick veneer is one brick thick (one wythe); for a solid wall two bricks thick, double the count.
Sources
- Technical Note 10: Dimensioning and Estimating Brick Masonry, Brick Industry Association, February 2009. Bricks per 100 sq ft of wall and cubic feet of mortar for each brick size and joint (Table 4).
- QUIKRETE Mortar Mix (No. 1102) and Mason Mix (No. 1136) data sheets, The QUIKRETE Companies, revised November 2020. An 80 lb bag lays up to 37 standard bricks or 13 standard 8 x 8 x 16 in blocks.