How cubic yards are worked out
Multiply the length and width in feet by the depth in feet, then divide by 27, the cubic feet in a cubic yard (3 feet by 3 by 3). A 20 by 10 foot area 4 inches deep is 20 × 10 × 4 ÷ 12 = 66.7 cubic feet, and 66.7 ÷ 27 = 2.47 cubic yards.
Cubic yards = length (ft) × width (ft) × depth (in) ÷ 12 ÷ 27Cubic meters = cubic yards × 0.7646What one cubic yard covers
| Depth | Square feet per cubic yard |
|---|---|
| 1 in | 324 |
| 2 in | 162 |
| 3 in | 108 |
| 4 in | 81 |
| 6 in | 54 |
| 8 in | 41 |
| 12 in | 27 |
A cubic yard spread 1 inch deep covers 324 square feet, so divide 324 by the depth in inches for any other depth.
Ordering
Suppliers sell dirt, mulch, sand and concrete by the cubic yard; gravel and stone can be sold by the ton, so ask the yard how many tons its stone weighs to the cubic yard. Loose material settles when it's spread and packed, which is what the extra is for. For a slab or footing, the concrete calculator also counts the bags of premix.
Common questions
How many cubic feet are in a cubic yard?
27: a cube 3 feet on each side.
How many cubic yards for a 10 by 10 area, 4 inches deep?
1.23 cubic yards: 10 × 10 × 4 ÷ 12 ÷ 27.
How many cubic yards in a ton?
It depends on the material's weight, so there's no single answer; the supplier's weight per cubic yard turns one into the other.