Foundation Wall Concrete Calculator

Estimate ready-mix volume for a poured foundation or stem wall. Enter the total wall length, height, and thickness to get cubic yards or cubic meters, including a waste allowance.

Foundation Wall Details

Total Wall Length (perimeter)

Wall Height

Wall Thickness

Waste / Overage

Enter your wall dimensions to see concrete volume needed.

The formula

Cubic Yards = (Wall Length ft × Height ft × Thickness in ÷ 12) ÷ 27

Use the total running length of all wall segments — for a rectangular foundation that’s the full perimeter. An 8-inch wall thickness is typical for residential foundations; 10–12 inches is common for taller walls or heavier loads.

Measuring perimeter correctly

Measure along the centerline of the wall rather than the outside face — on a full perimeter, using outside dimensions double-counts the corners slightly. For most estimates the difference is small, but on long runs it adds up to real yardage.

Frequently Asked Questions

How much concrete is in a foundation wall?

Multiply wall length by height by thickness (converted to feet) and divide by 27. A 140 ft perimeter wall, 4 ft tall and 8 in thick, is about 13.8 cubic yards before waste.

How thick should a poured foundation wall be?

Eight inches is the common residential standard. Taller walls, poor soils, or heavy backfill loads often call for 10–12 inches — check your local code and engineering.

Should I order extra concrete for a foundation pour?

Yes — 5–10% extra is standard. Foundation forms can bow slightly and footings below are rarely perfectly level, so the true volume usually exceeds the plan volume.