Brick & Block Calculator
Calculate masonry brick and concrete block counts with mortar joints and waste factors.
Last verified: September 2026Inputs & Parameters
Calculation Results
Actual brick, block, and mortar dimensions vary by manufacturer, product, and jurisdiction. Mortar quantity is an approximate planning estimate.
Masonry Estimation: Modular Bricks, CMU Blocks & Mortar
Masonry calculations derive unit counts directly from user-entered unit dimensions and mortar joint thickness. Preset configurations (such as modular brick or 8x8x16 CMU) provide convenience starting points while remaining fully editable to accommodate manufacturer variations.
Core Mathematical Formulas
- Effective Unit Face:
Face Area = (Unit Length + Joint) × (Unit Height + Joint) - Net Wall Area:
Net Area = (Wall Length × Height × Wall Count) - Openings Area - Derived Units per Area:
Density = 1 / Face Area - Recommended Units:
Units = CEILING(Net Area × Density × (1 + Waste% / 100)) - Approximate Mortar Bags: Planning estimate based on ~0.007 bags/brick (~7 bags per 1,000) or ~0.03 bags/block.
Worked Example
A modular brick wall measuring 20 ft long by 8 ft high (160 sq ft) with 7.625" × 2.25" bricks, 0.375" mortar joints, and 5% waste:
1. Effective Face = (8.00 / 12) × (2.625 / 12) = 0.1458 sq ft/unit
2. Density = 1 / 0.1458 = 6.86 units / sq ft
3. Theoretical Units = 160 × 6.86 = 1,097 units
4. Recommended Units with 5% Waste = 1,152 units (~8 mortar bags)
Assumptions & Limitations
Actual brick, block, and mortar dimensions vary by manufacturer, product line, and jurisdiction. Mortar bag quantities are approximate planning estimates. Structural rebar, grout core fills, bond beams, and wall ties must be calculated separately.