Calculators/ Concrete/Concrete Footing Calculator
Concrete Footing Calculator
Volume for strip footings and foundation trenches.
Concrete Footing Calculator
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in
in
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Footings spread the building load onto the soil. They are measured as a trench: total run length by width by depth. Enter the combined length of every footing run, including internal walls.
How this is calculated
- Volume = total length × width × depth, converting inches to feet.
- Add every footing run together first, including internal walls.
- Trench-dug footings need a larger waste allowance than formed ones, because soil walls collapse inward. Use 10-15% for a dug trench.
Frequently asked questions
How deep should a footing be?
Below the local frost line, which varies from a few inches in the south to over four feet in northern states. Always check your local building code.
How wide should a footing be?
A common rule is twice the width of the wall it supports, with 16 inches being typical for a standard 8 inch foundation wall.