How Much Gravel for an RV Pad or Parking Spot?

Updated 2026-09-18 · Yardly

Build an RV pad or parking spot with 6-8 inches of compacted crushed stone (8-11 for a heavy Class A), and order about 20-25% more loose volume than the finished bed — because a parked RV is a sustained static load that punches deeper than a passing car, and crusher run shrinks that much under a plate compactor. Here’s the formula, the depth-by-load rule, and the layered section that keeps a 30,000-lb motorhome from sinking into your yard.

The gravel formula for a pad

Same volume math as every Yardly gravel estimate, with a deeper compaction margin:

(Length × Width × Depth ÷ 12) ÷ 27 × 1.25 = loose cubic yards

The ”÷ 12” turns depth-in-inches into feet, ”÷ 27” converts cubic feet to cubic yards, and ”× 1.25” is the compaction margin — crusher run loses 20-25% of its loose volume under a plate compactor, so you order loose and finish at your target depth. The gravel calculator runs this and flips between yards and tons.

A worked example: a 12×40 ft RV pad at 8 inches

• 480 sq ft × (8 ÷ 12 ft) = 320 cu ft → ÷ 27 = 11.9 cu yd compacted
• × 1.25 = 14.8 loose cu yd → order ~15 yd³
• × 1.4 tons = ~21 tons of crusher run

That’s a bit more than one tandem-axle dump truck (10-14 yd). A lighter car pad at 6 inches on the same footprint would be about 11 loose yards / 15 tons.

Depth is set by load, and a parked RV is a heavy load

This is the part car-pad math gets wrong. A parking spot for a sedan can run 4-6 inches compacted. An RV is a different animal for two reasons: it’s heavy (8,000-30,000+ lb), and — unlike a car that drives over the stone — it sits in one spot for months, a sustained static load that slowly compresses and displaces aggregate. Builder guidance lands the range like this:

• Car / SUV pad: 4-6 inches compacted (Backyard Bases: 4 inches standard, 6 for heavier).
• RV / heavy vehicle: 6-8 inches minimum (Backyard Bases specs 6 for RVs); Hello Gravel pushes 8-11 for RVs and light commercial.
• Clay soil, soft ground, or freeze-thaw: take the deeper end and add geotextile fabric so the stone doesn’t sink into mud.

Build it in layers, not one pile

A pad’s top layer is the driving surface, so the material stack matters:

1. Stripped, compacted subgrade. Remove topsoil/organics down to mineral soil, then compact the native ground so nothing decomposes underneath.
2. Geotextile fabric on clay, wet, or soft soil — stops the stone from pumping down into mud.
3. Coarse structural base — 3-4 inches of #3/#4 crushed stone for load spread.
4. Binding layer — 2-3 inches of #57 or similar to fill the gaps.
5. Wear surface — 2-3 inches of crusher run that packs to a firm, drivable finish.

So an “8-inch” pad is really a coarse layer plus a finer layer, not 8 inches of one size. Compact each in 2-4 inch lifts with a plate compactor (rent the 90-lb class, not the 60-lb — the results are dramatically better).

Crown it so water runs off

Give the finished pad a slight crown — about ¼ inch of fall per foot from center to edge (roughly 2%). Pooled water softens the subgrade and is what turns a pad into a potholed mess within a season. A flat pad holds water; a crowned one sheds it.

What not to buy

The smooth rounded stuff — pea gravel, river rock, decorative stone — looks fine in a garden bed and fails under a tire. Rounded stone behaves like a box of marbles no matter how long you run the compactor; it never interlocks, so the surface migrates and settles. Use angular crushed stone for every structural layer, and reserve rounded decorative stone only for a thin top dressing you’ll rake back.

Keep reading

• Size the exact order in the gravel calculator from your pad dimensions and depth.
• Building a smaller static load instead? Gravel for a shed base covers the thinner section a shed needs.
• Comparing pad vs driveway depth? The gravel driveway calculator explains the layered base a driveway carries.

Frequently asked questions