Trench Spoil Volume Calculator
Estimate bank excavation, loose spoil volume, reusable material, hauled volume, full truckloads and disposal cost for a rectangular trench.
Default project preview
27.78 yd³
Bank excavation
22.22 yd³
Reused on site
8.33 yd³
Volume to haul
19.44 yd³
Truckloads
2
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Input and output guide
What each value means
The labels and units below are part of this calculator’s visible methodology. Replace every default with measurements or product data from the actual project.
Trench length
Enter this project assumption in ft. The current imperial default is 100 ft.
Average trench width
Enter this project assumption in ft. The current imperial default is 2 ft.
Average trench depth
Enter this project assumption in ft. The current imperial default is 3 ft.
Excavated swell
Enter this project assumption in %. The current imperial default is 25 %. Minimum: 0. Maximum: 80.
Loose spoil reused on site
Enter this project assumption in %. The current imperial default is 30 %. Minimum: 0. Maximum: 100.
Truck capacity
Enter this project assumption in yd³. The current imperial default is 10 yd³.
Cost per truckload
Enter this project assumption in a unitless value. The current imperial default is 325. Minimum: 0.
How to read the outputs
Bank excavation
in-place trench volume. Default preview: 22.22 yd³.
Reused on site
30% of loose spoil. Default preview: 8.33 yd³.
Volume to haul
after reuse. Default preview: 19.44 yd³.
Truckloads
rounded full loads. Default preview: 2.
Trench footprint
plan area. Default preview: 200 ft².
Haul cost
entered load rate. Default preview: $650.00.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Bank volume = length × width × depth. Loose spoil = bank volume × swell factor. Haul volume subtracts the entered reuse percentage, then truckloads are rounded up.
Reviewed project guidance
How to use this estimate in a real project
Last reviewed: August 19, 2026
Convert in-place trench excavation into loose spoil volume using swell, then estimate reusable spoil, hauled volume, truckloads and disposal cost.
Calculation steps
- 1Calculate bank excavation from average trench dimensions.
- 2Apply material swell after excavation to estimate loose spoil.
- 3Subtract only the loose spoil that can genuinely be reused on site.
- 4Divide haul volume by usable truck capacity and round to whole loads.
Worked numerical example
A 100 ft × 2 ft × 3 ft trench contains 600 ft³, or about 22.2 yd³ bank volume. With 25% swell, loose spoil is about 27.8 yd³. Reusing 30% leaves about 19.4 yd³ to haul, requiring two 10 yd³ truckloads.
Purchasing and rounding
Disposal pricing may be by truck, ton or volume. Confirm truck legal payload, disposal-site acceptance and whether wet/heavy soil reaches weight limits before nominal volume.
Interpret the result
Bank volume describes the excavation void; loose volume describes excavated material. Truckloads must be based on the loose hauled volume, not trench geometry.
Page-specific assumptions
- Average trench width/depth represent the run.
- Swell factor is appropriate for excavated material.
- Reuse percentage applies to loose spoil.
Common mistakes
- Applying swell to truck capacity instead of excavated material.
- Subtracting compacted backfill volume directly from loose spoil.
- Assuming every truck can carry its nominal volume of wet soil.
Primary and technical references
BuildMeter provides planning estimates, not engineering, architectural, electrical, mechanical, plumbing, permit or code approval. Review the methodology and verify final decisions with product documentation and qualified professionals.
BuildMeter Guides
Understand the measurements and assumptions
Use these visible reference guides before changing project inputs or planning allowances.
FAQ
Trench Spoil Volume Calculator questions
Why is loose spoil larger than the trench?+
Excavated soil expands because its in-place structure is disturbed and void space increases.
Can all excavated soil be reused as backfill?+
Not always. Material suitability, compaction requirements and displaced pipe or bedding volume affect reuse.
Does truck capacity equal legal payload?+
Not necessarily. Weight limits and material density may reduce the usable volume per load.