How Does Concrete Leveling Work for a Sunken Driveway?

Concrete leveling for a sunken driveway works by drilling holes in the settled slab and pumping a leveling material underneath to fill the empty space. As the material fills the void, it helps stabilize the underlying area and raises the slab toward the level of the surrounding concrete. Concrete leveling may be suitable for a slab that has settled in one piece. How long the repair lasts depends on the method used and whether the cause of settlement is addressed.The repair is more than simply filling a gap under the driveway. What happens beneath the slab, how the concrete responds as it is lifted, and what caused it to sink in the first place can all affect the result. At Lift It PRO, we look at these factors before lifting a driveway so you can understand whether leveling is suitable and what to expect from the repair. 

Why Did My Driveway Sink?

A driveway drops when the ground beneath it gives way, and soft or loosely packed soil is a common starting point. Concrete industry guidance says any pockets of soft soil that can't be compacted evenly should be dug out and replaced with something like compactable gravel before a slab is poured. Pavement guidance identifies inadequately compacted fill as one possible cause of localized settlement.

Directing downspout discharge away from the driveway can help reduce the risk of water undermining the soil beneath the slab.

Frost heave can occur when frost-susceptible soil contains sufficient moisture and temperatures fall low enough for freezing to occur. Clays, silts and very fine sands can heave. Sands and gravel generally don't.

What Is Concrete Jacking?

Concrete jacking, also called slab jacking, involves injecting grout or polyurethane beneath a settled slab to raise it toward the level of adjacent slabs. Mudjacking uses a cement-based slurry. Polyjacking, or foam jacking, uses expanding polyurethane foam, and that's the method we certainly use on driveways.

What Happens on Lift Day, Step by Step

1. Assess the slab. We check whether each sunken section is solid enough to lift and look for what caused the drop.

2. Drill the injection holes. Foam lifting uses holes about 5/8 inch across, while mudjacking holes run about 2 inches. Our FAQ explains how our foam-lifting process uses fewer, smaller holes than mudjacking.

3. Inject in small passes. We inject the material through several holes, a little at a time. The foam expands to fill the voids and pushes the slab up. Some pavement-repair guidance recommends limiting each lift to 1/4 inch to reduce the risk of cracking. The right lifting procedure depends on the slab and repair method.

4. Close up the holes. The smaller injection holes used for foam lifting help make the repair less noticeable.

Most of our jobs are completed in hours, not days, and the surface is ready to use immediately after the work. Our foam-lifting process also doesn't require heavy equipment.

Foam or Mudjacking for a Driveway?

Both methods can lift a slab, but they differ in injection-hole size, curing time, material and cost. Actual curing times depend on the product and conditions.

Factor	Polyurethane foam	Mudjacking
Hole size	About 5/8 inch	About 2 inches
Typical cure time	Under an hour	Up to 48 hours
Material	Lighter	Heavier cement-based slurry
Price	Higher	Lower

Cure time is one factor to consider if you need to use the driveway soon after the repair. For a closer look at both methods, read polyjacking vs. slabjacking.

Is Concrete Leveling for a Sunken Driveway Always Possible?

Not every sunken driveway is suitable for leveling. Solid concrete slabs may be raised and stabilized, while gravel and blacktop require replacement or reinstallation. A slab that is badly cracked may also be too damaged to lift.

If your driveway is concrete and the settled sections remain largely intact, we can assess whether lifting is appropriate. If the surface is asphalt or gravel, or the concrete is badly broken, replacement or another repair may be a better option.

Lifting isn't foolproof, either. A slab may not lift high enough, or it may break after it's raised and need to be replaced. We advertise savings of up to 50% compared with concrete replacement, but actual savings depend on the project.

Lift It PRO offers a two-year warranty for eligible concrete that is at least 10 years old. Before booking, ask us about the warranty requirements, exclusions, and maintenance conditions that apply to your project.

What You'll Do Afterward, and What to Ask Concrete Driveway Contractors

After the work is complete, seal repaired seams or backfill exposed edges as needed. For large cracks, follow our published maintenance instructions or ask us which preparation and sealant are appropriate for your repair.

Point your downspouts so water runs away from the slab. Water management and required maintenance are also warranty conditions. Review our FAQ page to understand the requirements that apply to your repair. Crack filling and resurfacing are also available as part of our driveway services.

Before you hire our concrete driveway contractors, ask which material they inject, what the warranty covers and requires from you, and whether they'd tell you if a section should be replaced instead.

Have Your Sunken Driveway Assessed 

After the next heavy rain, take a few minutes to note where water pools around the driveway and where each downspout empties. Water that repeatedly collects near the slab can affect the soil beneath it and may contribute to further settlement.

When you’re ready, request a free estimate for driveway concrete leveling. We can assess the condition of your driveway, determine whether the settled sections are suitable for lifting, and explain what repair options make sense for the slab.

We serve homeowners in York, Harrisburg, Lancaster, Hanover, Gettysburg and surrounding areas. If your driveway is sinking, uneven, or showing signs of settlement, getting it assessed can help you understand what is happening beneath the concrete before the problem gets worse.