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 capacity than the hole itself.
How it’s calculated
Bank volume = length × width × depth. Loose volume = bank × (1 + swell %), where the swell is your contractor’s figure for the ground. Loads = loose ÷ vehicle capacity.
Worked example
With these inputs:
- Length
- 10 m
- Width
- 6 m
- Depth
- 0.6 m
- Swell once dug (%)
- 0%
- Haul with
- 6 m³ skip
the result is:
- Loose spoil to remove
- 36 m³
- In-ground (bank) volume
- 36 m³
- Swell
- +0%
- 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.
- Find buried cables and pipes with a cable locator, and ask the municipality for its service plans, before digging.
- Check skip weight limits for soil.
Common questions
What is a swell factor?
How much more room soil takes once it is dug. Published tables disagree a lot (sand alone is given anywhere from about 5% to 50%), so use the figure your earthworks contractor or skip supplier works with for your ground.
Results are estimates for planning and pricing. Check quantities against your drawings, the manufacturer’s data and SANS 10400 (the National Building Regulations) and your local municipality before ordering.