Estimate the concrete blocks (CMU) and mortar bags needed for a wall from its length and height, minus openings, for US and metric block sizes.
About this tool
Estimate the concrete blocks and mortar needed for a wall.
How to use Concrete Block Calculator
- Enter the wall length and height and any door or window area.
- Choose the block size.
- Read the number of blocks and mortar bags.
Worked example
A 40 × 8 ft wall with standard 8 × 8 × 16 in blocks needs about 240 blocks and 8 bags of mortar mix, including 5% waste.
How many blocks are in 100 square feet?
About 113 standard 8 × 16 in blocks with 3/8 in joints.
Is grout for cores included?
No. Reinforced walls need extra grout to fill the block cores.
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