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CM into Inches
Construction · Calculator

Block Calculator

Calculate the number of concrete blocks needed for a wall.

Block Calculator

Estimate concrete blocks (CMU) required for your wall project.

Formula

Blocks = (Wall Area / Block Area) × 1.05

Step-by-step

  1. Compute wall area in sq inches
  2. Compute block area with mortar joint
  3. Divide and add 5% waste

Example

30×10 ft wall with standard 16×8 blocks = ~213 blocks.

FAQ

What is a standard CMU size?+

A standard concrete block is 16 × 8 inches (nominal).

Why add 5% extra?+

To account for cuts and breakage during installation.

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