Brick and CMU Count
Unit count from wall area, unit size, and mortar joint.
Example
You enter
- Wall area (ft²) 100
- Unit type cmu_8x8x16
- Mortar joint (in) 0.375
- Waste factor 0.05
You get
- Unit count (with 5% waste) 119
- Base count 113
- Face area per unit 0.889 ft^2
Checked against published worked examples from: Concrete Masonry & Hardscapes Association (NCMA); Brick Industry Association.
Details, formula, and sources
Formula or tableUnits = ceil(wall_area / laid module face) + ceil(that x waste), the module being the unit face plus one mortar joint each way. Modular brick lays three courses to 8 in (2-2/3 in course, 8 in length: 6.75 per ft^2, BIA Technical Note 10); standard brick 8 x 2-1/4 with 3/8 in joints is 6.55 per ft^2; an 8 x 16 CMU module is 1.125 per ft^2. Allow 5% breakage waste.
Source and editionBIA (Brick Industry Association) Technical Notes by name; NCMA TEK manuals by name.
Free accessBIA Tech Notes free at gobrick.com. NCMA TEK manuals free at ncma.org.
What governsEstimate. AHJ and licensed professional govern.
API field nameswall_area_ft2, unit_type, mortar_joint_in, waste_factor, unit_count, base_count, face_ft2
- Modular brick module 8 in long x 2-2/3 in course (three courses = 8 in), 21.3 in^2 laid faceBIA Tech Note 10