Retaining Wall Block Calculator
Number of blocks for a retaining wall.
Enter your wall length and height plus the block face size to get how many retaining-wall blocks to buy.
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Estimating wall blocks
Wall face area is length × height. Divide by one block’s face area (face length × height ÷ 144) and add 5%. Plan a buried base row and gravel backfill for drainage.
FAQ
How tall can I build without an engineer?
Many areas cap DIY segmental walls around 3–4 ft; taller walls often need engineering and a permit. Check local code.
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