How much gravel do I need for a 10×20 parking pad?
A 10×20 ft parking pad at 4 inches deep needs about 2.5 cubic yards of gravel — call it 3.5 tons. That’s a delivered-bulk quantity, not a bagged one, and a pad that lasts is built in layers.
For your area at 4″ deep, you need approximately 2.47 cubic yards of gravel — roughly 3.5 tons depending on the material.
Adjust These Numbers for Your ProjectThe math, step by step
- Your area: 10 × 20 = 200 sq. ft.
- At 4 inches deep: 200 × 0.333 = 66.7 cu. ft.
- Cubic yards: 66.7 ÷ 27 = 2.47 yd³
- Approximate weight: 2.47 × 1.4 = 3.5 tons
- Tonnage is approximate — density varies by material, moisture, and supplier.
- Gravel compacts — for driveways, plan the depth after compaction.
A parking pad that stays flat is two layers, not one: a 2–3 inch base of larger crushed stone (#3 or railroad ballast size) that locks together under load, topped with 2 inches of smaller crusher run or #57 that packs into a smooth driving surface. Single-layer pads of small gravel rut under tires within a season. If you’re pricing the real thing, run this calculator twice — once per layer depth — and order both sizes.
The “crushed vs. rounded” distinction matters more than the size number. Crushed stone has angular faces that interlock and stay put under a 4,000-lb vehicle; rounded river rock and pea gravel roll — they never fully compact and will migrate out from under tires. For anything a car parks on, crushed is the only correct answer.
At 3.5 tons, this is a dump-truck delivery, and most suppliers price by the ton with a delivery fee. Have the driver tailgate-spread along the pad’s length if the truck can access it — spreading 3.5 tons by wheelbarrow from a single pile is honestly a half-day of hard labor you can avoid with one sentence to the dispatcher.
Frequently asked questions
How many tons is a cubic yard of gravel?
Crushed stone runs about 1.4 tons per cubic yard dry. Suppliers sell by the ton or the yard — this calculator shows both so either quote is comparable.
Is 4 inches deep enough for parking?
Over firm, well-drained ground, yes — as two compacted layers. Over soft or clay soil, go 6 inches total and consider a geotextile fabric underneath to stop the stone sinking into the subgrade.
Do I need fabric under the gravel?
On clay or soft soil, landscape-grade geotextile roughly doubles pad life by keeping stone and soil separate. On sandy, well-drained ground it’s optional.