Concrete Block Calculator

Concrete masonry units for walls, with openings and waste.

Project measurements

Wall length (ft)

Wall height (ft)

Block thickness (CMU)

Door and window openings (SF)

Waste allowance (%)

How it’s calculated

Gross SF = length × height. Net SF = gross SF − openings. Blocks = round up(net SF × 1.125). Purchase = round up(net SF × 1.125 × waste factor).

Nominal CMU face dimensions are 8″ × 16″, including mortar joints. Thickness does not change the face-area calculation.

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Our free calculators are useful for quick quantity calculations. For a complete construction estimate, upload your drawings and let our team prepare a customized quotation.

Receive your customized quotation in less than 4 hours after submitting your drawings.

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