RV Pad Gravel Calculator
Estimate the gravel for an RV, camper or trailer pad. Enter the length, width and depth to get tons, cubic yards and cost — pre-set to a 6-inch road-base build, because an RV is far heavier than a car.
Sets a typical depth — tweak anything below.
For a 40 ft × 12 ft area at 6 in deep, order about 9.78 cubic yards (18.13 US tons) of class 5 / road base.
Estimates only. Densities vary by moisture, compaction and supplier — confirm quantities before ordering.
How much gravel do I need for an RV pad?
Multiply the pad's length by its width, multiply by the depth in feet, and divide by 27 for cubic yards. A 40 ft × 12 ft pad at 6 inches comes to about 8.9 cubic yards — roughly 16.5 tons of road base. That is a serious order: it's a full tandem dump-truck load, not something you haul in a pickup. Enter your own pad size above for the exact tonnage.
How thick should an RV pad be?
6 inches of compacted road base over firm ground, and 8 inches or more on soft or clay soil. Don't copy driveway numbers here — a car weighs around 4,000 lb spread over four tires, while a loaded fifth wheel runs 15,000–20,000 lb and a big motorhome can pass 30,000. Worse, a parked RV puts much of that through four small jack pads, so the load is concentrated rather than rolling. Four inches of stone that's fine under a sedan will dish and sink under a rig that sits in one spot all season.
How big should an RV pad be?
Measure your rig and add margin — the pad needs to be longer and wider than the RV itself. A typical travel trailer pad runs 10–12 ft wide by 30–35 ft long; a big fifth wheel or Class A wants 12 ft by 40 ft or more. Two things people forget: slide-outs extend 2–3 feet past the wall on one or both sides, and you want a couple of feet of stone under your feet where you step out the door, or you'll be stepping into mud. If you'll also park a tow vehicle alongside, add another 10 feet of width.
What gravel for an RV pad?
Road base — also sold as Class 5, crusher run, or 3/4 minus. It's crushed stone with the fines left in, so it compacts into a hard, load-bearing layer, which is exactly what a heavy rig needs. Clean stone like #57 has no fines and stays loose, so jack pads sink into it. Compact the base in 3-4 inch lifts, dampening each one, and crown the pad slightly or slope it about 1% so rain runs off instead of pooling under your RV. Some people finish with an inch of decorative stone on top — that's fine, as long as the compacted base is underneath.
RV pad size and depth guide
| Rig | Typical pad | Depth |
|---|---|---|
| Small trailer / pop-up | 10 × 25 ft | 4–6 in |
| Travel trailer | 10–12 × 30–35 ft | 6 in |
| Fifth wheel | 12 × 40 ft | 6 in |
| Class A motorhome | 12 × 40+ ft | 6–8 in |
| Any rig on soft/clay soil | as above | 8 in + geotextile |
Add room for slide-outs (2–3 ft per side) and a step-out area by the door. Add ~10 ft of width to park a tow vehicle alongside.
Worked examples
- 35 ft × 10 ft = 350 sq ft
- 350 × 6 in (0.5 ft) = 175 cu ft
- 175 ÷ 27 = 6.5 cubic yards
- × ~1.85 ton/yd³ ≈ 12 tons
- 40 ft × 12 ft = 480 sq ft
- 480 × 6 in (0.5 ft) = 240 cu ft
- 240 ÷ 27 = 8.9 cubic yards
- × ~1.85 ton/yd³ ≈ 16.5 tons
- 480 sq ft × 8 in (0.67 ft) = 320 cu ft
- 320 ÷ 27 = 11.9 cubic yards
- × ~1.85 ton/yd³ ≈ 22 tons
- + geotextile under the base
Common mistakes to avoid
- Building it like a car driveway. A loaded RV can weigh five times a car and parks in one spot for months. 4 inches is a driveway number; an RV pad wants 6, or 8 on soft ground.
- Using clean stone with no fines. #57 and other washed stone never packs hard, so jack pads and tires sink into it. Use road base / crusher run, which has fines and compacts.
- Forgetting slide-outs and the door. Slides reach 2–3 ft past the wall and you have to step out somewhere. Size the pad to the rig plus margin, not to the rig's footprint.
- No slope or crown. A flat pad holds water under the RV. Crown it slightly or slope it about 1% so rain drains away.
- Dumping it all in one layer. Six inches of stone dumped at once won't compact through. Build it in 3–4 inch lifts, dampen each, and compact before adding the next.
Frequently asked questions
How much gravel for an RV pad?+
A 40 ft × 12 ft pad at 6 inches deep needs about 9 cubic yards, roughly 16.5 tons of road base. Enter your own pad dimensions above for the exact amount.
How thick should a gravel RV pad be?+
6 inches of compacted road base on firm ground, 8 inches or more on soft or clay soil. Don't use the 4-inch figure from driveway guides — an RV is far heavier and parks in one place for months.
How big should an RV pad be?+
A travel trailer usually wants 10–12 ft × 30–35 ft; a fifth wheel or Class A wants 12 × 40 ft or bigger. Add 2–3 ft for slide-outs, room to step out the door, and about 10 more feet of width if a tow vehicle parks alongside.
What kind of gravel is best for an RV pad?+
Road base — Class 5, crusher run, or 3/4 minus. The fines let it compact into a hard, load-bearing surface. Avoid clean, washed stone like #57, which stays loose and lets jack pads sink.
Do I need fabric under an RV pad?+
On firm ground, no. On soft or clay soil, yes — a woven geotextile under the base stops the stone from being pumped down into the mud under load, which is the usual reason a pad goes soft and dishes after a wet season.