Block Wall Calculator

This calculator helps contractors and masons estimate CMU blocks and mortar for masonry wall projects. Enter your wall dimensions and opening counts to get accurate material quantities.

1. Enter wall length and height in feet: Measure the total length and height of your wall. For walls with sections at different heights, calculate each section separately.
2. Select block size: 8x8x16 is standard for most walls. Use 12x8x16 for taller walls or structural applications. Use 8x4x16 half-high for decorative or matching purposes.
3. Enter door and window counts: Standard door opening is 3x7 ft (21 sq ft) and standard window is 3x4 ft (12 sq ft). These are subtracted from the gross wall area.
4. Adjust waste percentage: Default is 10% for typical projects. Increase to 15% for complex layouts with many cuts.
5. Review results: See block count, mortar bags needed, and course count. Order lintel blocks and bond beam blocks separately.

Formula: Blocks = Net Area (sq ft) x Blocks Per Sq Ft x (1 + Waste %)