CalcExcavation Volume Calculator
Last updated: 2026-05-09
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| length | width | height |
|---|---|---|
| 3 | 2 | 0.1 |
| 4 | 3 | 0.1 |
| 5 | 4 | 0.12 |
| 6 | 4 | 0.12 |
| 8 | 5 | 0.15 |
What is Excavation Volume?
Excavation volume is the amount of soil that must be removed when digging for foundations, basements, trenches, or earthworks. The calculator computes both the in-situ (bank) volume and the bulked (loose) volume after excavation, accounting for the swell factor.
Volume Calculation
Net volume = Length × Width × Depth
Loose volume = Net volume × Swell factor
Swell factors: clay 1.25-1.40, sand 1.10-1.15, rock 1.40-1.60. The calculator estimates truck loads for disposal based on 8 m³ per truck.
Worked Example
Pit 10m × 6m × 1.5m, swell factor 1.25:
- Net volume = 10 × 6 × 1.5 = 90 m³
- Loose volume = 90 × 1.25 = 112.5 m³
- Truck loads = 112.5 ÷ 8 = 15 trucks (round up)
- Slope perimeter = 2(10+6) × 1.5 = 48 m² for shoring estimate
Common Mistakes
- Not accounting for the swell factor when ordering transport
- Insufficient shoring or sloping for deep excavations (safety risk)
- Forgetting extra workspace for formwork placement
- Not considering groundwater dewatering requirements
Standards
Calculated per CTE DB-SE-C. Safety slopes: 1:1 for stable soil, 1.5:1 for loose soil.
Frequently Asked Questions
Soil expands when excavated. The swell factor converts compacted in-situ volume to loose volume for transport. Clay swells 25-40%, sand 10-15%, rock 40-60%.
Any excavation deeper than 1.25m requires shoring or sloping per safety regulations. The calculator estimates slope perimeter for planning.
Clean soil can be reused on-site for backfill or grading. Contaminated soil requires certified disposal. The truck count helps estimate removal costs.