Foam: 15–30 minutes. Mudjacking: 24–72 hours. The cure-time gap between the two methods is the most practical difference in concrete lifting — here's how to plan around it.
Polyurethane foam: drive on it 15–30 minutes after the crew finishes. The foam cures through a chemical reaction, not by drying, so it's at full strength almost immediately. Mudjacking: wait 24–72 hours. The cement-based slurry needs real cure time to gain strength, and loading it early can crack the fill or push the slab back down.
This isn't a minor footnote — for a driveway or garage floor, it's often the deciding factor between the two methods. Everything else being equal, foam lets you use your driveway the same afternoon; mudjacking asks you to park on the street for a couple of days.
It comes down to chemistry. Polyurethane foam is a two-part chemical system: when the components mix at the injection gun, they react, expand, and harden in minutes. The reaction even generates its own heat, which is why foam works in winter. There's nothing to "dry" — the material is done when the reaction is done.
Mudjacking slurry is cement-based: a mix of cement, soil or sand, and water that hardens the way concrete hardens — through hydration, a slower chemical process that needs time and decent conditions. Rush it and you get weak fill. The full mechanics are in our how concrete lifting works guide; the practical upshot is patience.
| Milestone | Polyurethane foam | Mudjacking |
|---|---|---|
| Walk on it | Immediately | A few hours |
| Drive on it | 15–30 minutes | 24–72 hours |
| Full load (heavy vehicles, RVs) | Same day | 72+ hours — ask your contractor |
| Caulk the joints | Same visit (crew usually does it) | Same visit or next day |
| Apply surface sealer | After patched holes cure — a few days | After patched holes cure — a few days |
Note the joint-caulking row: sealing happens immediately with both methods. Don't confuse "wait to drive on it" with "wait to seal it" — open joints are how water gets back under the slab, and the first rainstorm doesn't care about your cure schedule. Our after-lift guide covers the full maintenance routine.
Cost comparisons ($3–$8/sq ft mudjacking vs. $5–$25 foam) usually dominate the foam-vs-mudjacking debate — see our full comparison. But run the real math on your situation: if mudjacking saves you $800 but costs you three days of street parking, a missed work-from-home setup, or a commercial lot sitting idle, foam's premium pays for itself. The cheapest method is the one that fits your life, not just the quote sheet.
About 15–30 minutes after the injection is complete. The foam cures through a fast chemical reaction — not by drying — so it's load-bearing almost immediately. Most contractors will have you pull the car back into the garage before they leave. This is the single biggest practical advantage of foam for driveways and garage floors.
Plan on 24–72 hours. The cement slurry needs time to cure and gain strength, and driving on it too early can crack the fresh fill or re-compress the slab. Your contractor will give you a specific window based on the mix, the weather, and the thickness of the lift — follow it, because the lower end of that range assumes decent conditions.
With foam, yes — immediately. With mudjacking, foot traffic is usually fine within a few hours, well before vehicles. If the lifted area is a walkway or porch rather than a driveway, mudjacking's cure time is much less of an inconvenience: you can use the front door the same evening and just keep the car off the driveway section for a day or two.
For foam, barely — the reaction generates its own heat, which is why foam is the winter method (see our cold-weather guide). For mudjacking, yes: cold slows the cement cure, pushing you toward the long end of the 24–72 hour window or beyond. A mudjacking job done in late fall needs more patience than the same job in July.
As soon as the lift is complete — the crew often caulks the same visit. There's no reason to wait: sealing the joints immediately keeps the next rainstorm from washing water back under the slab. If your contractor doesn't include caulking, do it yourself within a day or two with self-leveling polyurethane sealant. Details in our after-lift maintenance guide.
You risk undoing the work. The uncured slurry can compress under vehicle weight, the slab can settle back down, and the fresh fill can crack — turning a one-visit fix into a callback. If your schedule can't absorb 24–72 hours without the driveway, say so up front: that's exactly the situation where paying the premium for foam earns its keep.
Related reading: Mudjacking vs. foam · Winter concrete lifting · Sealing lifted concrete
Tell us your timeline on the quote form — a local specialist will recommend the method that fits your schedule, not just the cheapest one.