How it works
Use Fill a hole for an excavation, old pool or low spot: enter its length, width and average depth. Use Regrade a slope to build up a yard that should fall away from the house: enter the fill depth at the high end and the low end, and the calculator averages them as a straight wedge.
Dirt fluffs up when it is dug and loaded, then settles when it is spread and compacted. The compaction factor adds loose volume to cover that. Sandy fill needs about 10% to 15% extra; clay-heavy fill 20% to 30%. Compact in 6 to 8 inch lifts with a plate compactor or roller for the least settling.
Fill is sold by the loose cubic yard and delivered by truckload. Finish the top 4 to 6 inches with topsoil rather than fill if you plan to grow grass.
Formula
In-place cu yd = length × width × average depth (ft) ÷ 27. Regrade average depth = (high-end depth + low-end depth) ÷ 2. Loose cu yd = in-place × (1 + compaction factor).
Questions people ask
What compaction factor should I use for fill dirt?
Around 10% to 15% for sandy or granular fill and 20% to 30% for clay. If the fill will be machine-compacted in thin lifts, use the higher number because it packs down more.
How much fill does it take to fill an in-ground pool?
A 30 × 15 ft pool averaging 5 ft deep holds about 83 cubic yards in place. With 20% compaction that is 100 loose yards, or 10 ten-yard truckloads.
How much should the yard slope away from the house?
The International Residential Code calls for the ground to fall at least 6 inches within the first 10 feet from the foundation, a 5% slope.
How much does a dump truck hold?
A single-axle dump truck carries about 5 to 6 cubic yards; a tandem or tri-axle 10 to 16 yards. With wet soil, weight limits often govern before volume.