How it's calculated
weight = volume(ft³) × density(lb/ft³)
volume in cubic feet, density = material weight per cubic foot (lb/ft³). Reverse: volume = weight ÷ density.
Worked examples
| Material | Density (lb/ft³) | Weight of 1 ft³ |
|---|---|---|
| Water | 62.43 | 62.43 lb |
| Sand | 100 | 100 lb |
| Concrete | 150 | 150 lb |
| Granite | 168 | 168 lb |
Common questions
Why does the same volume weigh different amounts?
Weight depends on density, not just volume. A cubic foot of granite packs far more mass than a cubic foot of sand, so it weighs more.
How much does a cubic foot of water weigh?
About 62.43 pounds at room temperature. That figure is the baseline the other materials are compared against.