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Excavation Calculator — swell, haul and backfill

Bank, loose and compacted volumes for an excavation: how much you dig, how much you haul, and why the hole will not fill itself.

Excavation Calculator — swell, haul and backfill

The hole, the truck and the backfill are three different volumes of the same dirt. Soil expands when you dig it and shrinks when you compact it, and both directions cost money.

bank — in the ground loose — on the truck compacted — back in the hole
One pile of dirt, three volumes. It swells coming out and shrinks going back, which is why the hole you dug will not fill itself.
Bank volume (the hole)
Loose volume (on the truck)
Truck loads out
Backfill needed, compacted
Bank volume to supply that backfill
Net import / export

Three volumes, one pile of dirt. Bank is soil in the ground — the hole you measured. Loose is the same soil after digging, which occupies more space: that is swell, and it is what you pay to haul. Compacted is soil placed and rolled back down, which occupies less than bank: that is shrinkage, and it is why filling a hole takes more dirt than came out of it.

Swell and shrinkage figures vary widely with soil, moisture and compaction effort — the values here are ordinary planning ranges, not measurements of your site. On anything where the earthwork balance matters, use the factors from your geotechnical report. Truck loads assume about 12 yd³ per load, which changes with the truck and with local weight limits.