RVs, boats, and work trucks punish concrete that was never poured for them. Here's why heavy loads sink pads, which lifting method holds up under the weight, and when a pad is past lifting.
Most residential concrete is built for passenger cars — a few thousand pounds spread across four tires, parked in the same spot for years without complaint. An RV changes that equation completely. A mid-size travel trailer runs 5,000 to 8,000 pounds; a Class A motorhome can top 20,000 to 30,000 pounds. And unlike a car, that weight doesn't sit evenly: it concentrates at axle points, tongue jacks, and stabilizer feet, where a few square inches of steel press down on one spot of slab, day after day, season after season.
The slab usually isn't the first thing to fail. The soil under it is. Utah soils — especially the clay pockets common across the Salt Lake Valley — compress under sustained heavy load, and once the soil gives a little, water finds the low spot, erosion widens the gap, and the pad starts its slow tilt. Add Utah's freeze–thaw cycle on top, and a pad that was level when the RV first parked there can be down an inch or two within a few years. The same forces behind why Utah concrete settles generally hit heavy pads harder and faster.
Side-yard RV pads are the worst offenders, and not by accident. Many were poured as an afterthought — a thin extension of the driveway, or a homeowner weekend pour over ground that was never properly compacted. They were never engineered for a 10,000-pound trailer, and the soil beneath them was never prepared for one either. When owners ask why the main driveway is fine but the RV pad sank, the answer is usually that the pad was a lighter build carrying a heavier load on weaker ground.
Not every low spot on a pad is the same problem, and the pattern tells you a lot before anyone quotes:
One warning sign overrides all of these: a slab that is crumbling, spalling apart, or broken into pieces that rock independently when you step on them. That concrete is done. Lifting it is lifting rubble, and the money is better spent on a new pour built for the load.
Both methods lift a pad. Under heavy loads, they are not equal — and the difference is about weight, not just price.
Foam weighs almost nothing — a few pounds per cubic foot versus roughly 100 pounds per cubic foot for cured slurry. On soil that already failed under a heavy vehicle, adding as little weight as possible is a genuine engineering advantage, not marketing. Foam is also waterproof, so spring snowmelt can't erode it, and it cures in 15–30 minutes, so the RV can go back sooner. Its weaknesses: higher cost ($5–$25 per square foot) and, on very large pads, a total that climbs fast.
Slurry at $3–$8 per square foot is the economical way to lift a big pad, and on firm, well-drained soil it holds up fine. The caveat is the one that matters here: you're adding a heavy material on top of soil that just proved it can't carry weight. On clay or saturated ground, that extra load can shorten the repair's life. It also needs about 24 hours before the RV rolls back on.
The honest summary: on a big pad over decent soil, mudjacking's savings are real and defensible. On clay soil, soft ground, or a pad that has already been lifted once, foam's light weight is worth the premium. The full trade-off is laid out in mudjacking vs. foam, and a contractor who can explain which side of that line your pad falls on is one worth listening to.
RV pads are priced like any flatwork: by area, by how far the slab has dropped, and by method. There is no special "RV rate" — a pad is a slab. Use the driveway numbers as your anchor, since pads and driveways are the same kind of job:
| Project | Mudjacking | Foam leveling |
|---|---|---|
| Driveway section (~220 sq ft) | $650–$1,300 | $1,500–$3,200 |
| Full driveway (~500 sq ft) | $1,500–$2,900 | $3,200–$7,200 |
Most residential jobs of this type land between $500 and $3,000 total, and most contractors carry a $300–$500 minimum charge. A pad that has dropped several inches needs more material than one down half an inch, so depth matters as much as square footage. The complete tables — including sidewalks, steps, and garage floors — are in the cost guide.
Lifting restores the slab; it doesn't change what the RV weighs. Four habits decide whether this lift is the last one for a decade or the first of several:
One more practical point: the RV has to be off the pad for the job, and the crew needs room to work around the whole slab, not just the low corner. Move the trailer, the boat, and the stack of firewood before the appointment, and confirm access for the pump rig — side yards with gates too narrow for equipment are a common reason jobs get rescheduled.
For most sinking RV pads, though, the story is simpler: a heavy load, soft Utah soil, and a few winters did what they always do. A lift puts it right for a fraction of replacement cost — and with foam under it and the water handled, it tends to stay right. Driveway repair follows the same logic, and the same pricing.
Yes, if the slab is still intact. A pad that has settled under heavy loads is a normal lift job — the same mudjacking or foam leveling used on driveways. If the concrete is shattered into shifting pieces, though, lifting stops making sense and replacement is the honest answer.
Foam has a real advantage here: it adds almost no weight to soil that already failed under load, and it won't wash out. Mudjacking costs less and works fine on large pads, but the slurry is heavy — on weak or clay soil, that extra weight is a genuine drawback. See the full comparison.
Use the driveway pricing as the guide: a driveway section (~220 sq ft) runs $650–$1,300 mudjacking or $1,500–$3,200 foam, and a full driveway (~500 sq ft) runs $1,500–$2,900 mudjacking or $3,200–$7,200 foam. Pads are priced by area and drop depth like any flatwork — see the cost guide.
It can, if nothing else changes. The fix that lasts pairs the lift with the cause: better drainage, a stable base where possible, and spreading the load (pads under jacks and stabilizers, not bare feet on concrete). A contractor who only quotes the lift and won't talk about load and water is selling half a repair.
No — the vehicle has to be moved off the slab before any lift, and it stays off until cure is complete: 15–30 minutes for foam, about 24 hours for mudjacking. Plan the parking shuffle before the crew arrives.
Not usually. Lifting restores the existing slab to grade; it doesn't thicken it. If the original slab was poured too thin for the load — a common story on side-yard RV pads — a contractor may flag that the slab will always be marginal for the weight. That's a judgment call worth hearing, not a sales pitch to dismiss.
Tell us what's parked on it, how far it's dropped, and where — a local specialist will give you a straight answer and a written estimate.