Concrete leveling
Foam Injection (Polyjacking) in Rockford, IL
Updated October 1, 2026
Foam is the newer of the two methods and, slab for slab, the one that holds up longest. It costs more per square foot, and on most of the jobs this site sees, that cost difference buys something real.
Cause
Why This One Settles
This page is about the method itself: foam is usually the better call wherever water is the actual cause, which on the evidence of this site's own town pages is most of the time.
- The two-part polyurethane expands as it reacts, filling the void and lifting the slab without the added weight a slurry carries.
- It cures chemically within minutes, which is why a foam-lifted driveway can be driven on the same morning rather than waiting out the day.
- The holes are roughly the size of a penny, smaller than mudjacking needs, because the foam does not require the same bore to flow.
- It does not wash out, so where the original void was caused by moving water, foam stays where it was injected instead of eroding the same way the soil did.
The underlying reason any of it moves here is the frost line. Rockford requires footings at 42 inches because the ground freezes that deep, and flatwork is poured well above it. Full explanation on why concrete sinks in Rockford.
The work
How This Job Runs
- Step 1
Confirm the void and mark every panel that has moved, same as any leveling visit.
- Step 2
Drill penny-sized holes across the settled area.
- Step 3
Inject the two-part foam in stages, watching the slab rise with a level as the material expands.
- Step 4
Patch the holes once level; the slab is ready for weight within minutes of the last injection.
When lifting is the wrong call
Where This Does Not Work
Foam is not worth the extra cost on a large, stable slab that settled once years ago and has not moved since, where mudjacking's lower price and comparable 5-to-10-year life cover the job just as well. Paying foam prices everywhere is not the honest answer any more than mudjacking everywhere is.
Cost
What It Runs
Foam injection runs $5 to $25 per square foot, roughly double mudjacking, and typically holds 10 to 15 years against mudjacking's 5 to 10. The full side-by-side, including when the cheaper method is still the right call, is on mudjacking versus foam.
Full per-square-foot breakdown and the comparison against replacement is on the pricing page, and the method choice is covered on mudjacking versus foam.
By town
Foam Injection (Polyjacking) Near You
What the concrete is like varies more across this metro than people expect.
Need foam injection (polyjacking) in the Rockford area?
Send a photo of the slab and roughly how far it has dropped. You get a fixed quote back.