Polyurethane concrete lifting, also called foam jacking or slab jacking, is a repair method that raises sunken concrete without removing it. We drill small holes into the slab and inject a two-part polyurethane material underneath. The two components react and expand, filling the voids and gently pushing the slab back to level.

Once the two liquid components meet at the injection point, a chemical reaction begins that causes the material to expand many times its original volume within seconds. That expansion fills gaps in the soil, compacts loose material underneath, and creates enough controlled pressure to raise the concrete evenly. We monitor the lift the entire time and stop injecting the moment the slab reaches the correct height.

Most residential jobs, sidewalks, driveways, patios, and porches, are done in a few hours. The foam itself cures in about 15 minutes, so you can walk on the repaired area the same day. Larger commercial or municipal jobs may take longer depending on the size of the area and the amount of lift needed.

Not necessarily. As long as we have access to the area being lifted, most residential jobs can be completed without you present. We will walk you through the assessment and quote ahead of time so there are no surprises on repair day.

Cost depends on the size of the area, how much the slab has settled, how much material is needed to fill the voids underneath, and how accessible the site is. It is almost always less expensive than tearing out and repouring the same section of concrete, since you are paying to fix the existing slab rather than replace it. Text us a photo for a free, no-obligation quote specific to your project.

Material for material, polyurethane usually costs more upfront than a cement-based mudjacking slurry. But because foam jobs use a small fraction of the material volume, cure almost immediately, and tend to hold their lift far longer, most property owners find the total value works out in favor of polyurethane, especially once you factor in fewer repeat repairs down the road.

Yes. Text a photo of the area you are concerned about to (443) 417-7347 and we will typically get back to you with an assessment the same day.

When installed correctly, a polyurethane repair can last for decades. The material is chemically inert once cured, meaning it does not absorb water, break down, or feed erosion the way a cement slurry can over time.

Yes. Once cured, high-density polyurethane foam is inert and does not leach into surrounding soil or groundwater. It also weighs a fraction of what a mudjacking slurry weighs, so it adds minimal load to soil that is often already struggling to support the slab above it. The injection holes are small, typically around ⅝ inch, so there is very little disruption to surrounding grass or landscaping.

High-density structural polyurethane is engineered to support heavy loads, from everyday foot traffic on a sidewalk to vehicle and equipment traffic on commercial and industrial slabs. The right density is selected based on what the slab needs to carry long term.

The injection holes, usually about the size of a dime or smaller, are patched and finished to blend in with the surrounding slab. Once the patch cures, most people cannot tell where the injection points were.

Polyurethane foam is not water-sensitive the way a mudjacking slurry is, and it can be installed across a wide range of temperatures. Our technicians will let you know if weather conditions on a given day call for rescheduling, but in general, our repairs hold up well through freeze-thaw cycles common to the Mid-Atlantic.

Almost any settled slab-on-grade concrete that is still structurally sound, including sidewalks, driveways, garage floors, patios, pool decks, porches, steps, warehouse floors, loading docks, and parking areas. If you are not sure whether your slab qualifies, send us a photo and we will tell you honestly.

In many cases, yes. Lifting a settled slab back to level can close gaps and reduce further movement, though existing cracks may still be visible afterward. During your assessment, we will tell you whether lifting alone will solve the problem or whether additional repair is needed.

No. We work with residential homeowners, commercial property owners, HOA boards, and municipalities. Commercial and municipal clients often choose polyurethane specifically because it minimizes downtime and disruption to tenants, customers, or the public while still meeting safety and compliance standards.

Confirm that the company is properly licensed and insured in your state, and ask what type of polyurethane system they use. Not all foams are formulated the same way, and systems designed specifically for geotechnical and structural applications perform differently than general-purpose expanding foam. State Line Concrete Lifting is licensed in Pennsylvania, Maryland, and Delaware (MD #161857, PA #PA15382, DE #2019701377).

We serve York County and the wider south-central Pennsylvania region, Harford and Cecil counties in Maryland, northern Delaware, and parts of southern New Jersey. Check our service area pages for a full list of towns, or just reach out, we are happy to tell you directly.