How to use it
- Enter the length and width of the area and the thickness after compaction.
- Choose the material: sand, gravel, crushed stone, ballast or topsoil.
- Order the weight shown; quarries sell by the ton, and the loose material settles when you compact it.
Worked example
A 10 × 5 m base of crushed stone, 200 mm thick when compacted, is 10 m³ compacted. Crushed stone loses about 25% of its volume under the roller, so you need 12.5 m³ loose, which at 1.6 t/m³ is 20 tonnes.
Typical thicknesses
Garden paths need 100–150 mm of compacted crushed stone, patios 150 mm and driveways for cars 200–300 mm, laid and compacted in layers of no more than 150 mm.
Frequently asked questions
How much does a cubic yard of gravel weigh?
About 1.3–1.5 US tons loose, depending on the size and moisture of the stone.
How much extra gravel should I order for compaction?
Crushed stone compacts by about 20–25%, sand by 10–15%. The calculator adds this allowance for the material you choose.