Backfill Calculator
Estimate backfill material needed for an excavation.
How It Works
Net volume = Excavation − Structure. Backfill = Net × (1 + Compaction ÷ 100).
Example
100 cu yd excavation with 40 cu yd of structure at 10% compaction: 60 × 1.1 = 66 cu yd.
Frequently Asked Questions
What is the structure volume?
The volume of the foundation, pipe, or wall that fills part of the hole and will not need backfill.
Why a compaction factor?
Backfill compacts to a smaller volume, so you order extra to end up at the desired grade.
What is a typical compaction factor?
10–20% is common, depending on the material and how much it is compacted.