Fill Dirt: Weight, Compaction & Uses
Structural fill for grading, foundations, and low-spot repair.
Fill dirt is unscreened subsoil used for structural fill — not for growing. It's cheaper than topsoil and compacts well beneath foundations, driveways, and grading projects.
Weight
~2,000–2,700 lb per cubic yard
Density
75–100 lb/ft³
Coverage
Fill compacts ~10–15%. Order that much extra above your calculated volume.
How do I calculate how much fill dirt I need?
Bulk fill dirt weighs ~2,000–2,700 lb per cubic yard depending on moisture and clay content. Compact in 6–8″ lifts with a plate compactor or jumping jack — filling too deep in one pass leaves voids that settle later.
For lawn areas over fill, cap with 4–6″ of screened topsoil. Never build over uncompacted fill.
What is fill dirt used for?
- Grading and leveling
- Filling low spots or old pools
- Building up around foundations
- Berms and retaining wall backfill
Which types of fill dirt are there?
Clean fill
No rocks, roots, or debris. Suitable near foundations.
Common fill
May contain small rocks and clumps. Rough grading.
Structural fill
Engineered gradation, compacts to spec. Under slabs and footings.
What else do people ask about fill dirt?
Is fill dirt the same as topsoil?
No. Fill dirt is subsoil for structural fill; topsoil is for growing plants.
How much does a yard of fill dirt weigh?
2,000–2,700 lb, higher when wet.
How do you compact fill dirt?
In 6–8 inch lifts with a plate compactor or jumping jack, at optimum moisture.