cubic foot
VolumeSection modulusexact by definition
The cubic foot is the volume of a cube one foot on a side, exactly 0.028316846592 m³ or about 28.32 litres. It is the standard unit for airflow (as cubic feet per minute), natural gas billing and appliance capacity in the United States. The factor is exact by definition.
Watch out: Gas volumes in cubic feet are only meaningful with a stated pressure and temperature, since a gas has no fixed volume. Utility billing uses standard or normal conditions and then converts to energy, which is why a gas bill shows therms or MJ alongside the volume.
| 1 ft³ (Volume) | 28.316847 L |
| 1 ft³ (Section modulus) | 28,316,847 mm³ |
The cubic foot is exactly 0.028316846592 m³. As a section modulus it appears in large concrete and masonry sections worked in feet, where in³ would run to six digits.