About this calculator
How much material comes out of a hole, a trench or a reduced-level dig. The ground “swells” once it is dug, so it fills more skip and lorry capacity than the hole itself.
How it’s calculated
Bank volume = length × width × depth. Loose volume = bank × swell factor. Loads = loose ÷ vehicle capacity.
Worked example
With these inputs:
- Length
- 10 m
- Width
- 6 m
- Depth
- 0.6 m
- Soil type
- Common earth / loam (+25%)
- Haul with
- 8 yd skip (6.1 m³)
the result is:
- Loose spoil to remove
- 45 m³
- In-ground (bank) volume
- 36 m³
- Swell
- +25%
- Approx. weight
- 57.6 t
Tips from the trade
- Most hauliers charge by load or by weight. Clay is heavy, so check weight limits.
- Keep clean topsoil separate. It’s worth money for regrading.
- Check for services with a CAT scanner and utility plans before digging.
Common questions
What is a swell factor?
The ratio of loose volume to in-ground volume. Common earth swells about 25%, clay 30–40% and rock 50% or more.
Results are estimates for planning and pricing. Check quantities against your drawings, the manufacturer’s data and the Building Regulations before ordering.