Concrete Resurfacing vs. Concrete Raising: What's the Difference?

Concrete resurfacing and concrete raising solve different problems. Resurfacing adds a thin new layer to the top of an existing slab to renew a worn or flaking surface. Concrete raising lifts a slab that has sunk by pumping material underneath it. If your concrete is both sunken and worn, the slab may need to be raised before it is resurfaced. Knowing the difference can help you understand which repair to consider.

Concrete Resurfacing vs. Concrete Raising: What’s the Difference? 

Resurfacing changes the surface. A thin layer of cement-based material, plain, latex-modified or polymer-modified, is bonded to the cleaned slab, while the old slab stays in place. Raising changes the slab's position: material is injected beneath it under pressure to lift it, fill the voids under it, or both. Neither one does the other's job, resurfacing repairs surface wear, while raising corrects the slab’s height.How Does Concrete Raising Work? 

Slabs usually sink because the soil under them was poorly compacted, shrank as it dried, or eroded away. Concrete raising, also called slabjacking, deals with the result. Crews drill holes through the slab and pump material underneath until it lifts and the voids beneath it are filled.

Hole size depends on the material. Foam typically needs holes 1/2 to 3/4 inch wide, while cement grout, the material used in mudjacking, typically needs holes of 1-1/2 to 2-1/2 inches. At Lift It PRO, we use polyurethane foam that enters as a liquid and hardens beneath the slab. Our foam is lighter than mudjacking material and requires fewer, smaller holes.

What Can and Can’t Concrete Resurfacing Fix?

Concrete resurfacing repairs wear on the top of a slab. It can help with scaling, which is the flaking or peeling of the concrete surface caused mainly by repeated freezing and thawing. Deicing chemicals add to the damage, especially when they're overused.

The new layer is only as strong as the concrete it's bonded to, so the base has to be sound before any material goes on. Engineering guidance for road pavements takes the same line. It reserves bonded resurfacing for concrete in good structural condition, where the new layer removes surface problems and the old slab still carries much of the load. 

Can You Resurface a Sunken Slab Instead of Raising It?

Not as a fix for the sinking. Resurfacing covers the top of the concrete but does not lift a sunken slab. A bonded layer depends on what's underneath it. Federal highway guidance says voids under an existing slab should be stabilized before a bonded overlay goes on, so the support is uniform. Cracks that are still moving tend to show up again in the new layer, and movement underneath can contribute to it losing its bond.

If the slab has sunk, deal with the support underneath first by raising it. Resurface it afterward only if the surface still needs repair. The American Concrete Institute's slabjacking guidance names a polymer-modified topping as one way to even out the look after a slab has been raised.

Which Fix Matches Your Concrete Problem? 

Use this as a starting point. An on-site inspection can help determine which repair is appropriate. 

What You See	Likely Fix	Why
A slab has sunk or tilts, leaving a step at a joint	Concrete raising	Raising lifts the slab and fills the voids beneath it
The surface is flaking or peeling after a few winters	Resurfacing, if the slab is sound	Scaling is surface damage, and the new layer needs a sound base
A sunken slab with a worn surface	Raise first, then resurface	Voids should be stabilized before a bonded layer goes on
A badly cracked or broken slab	Ask about other repairs	Badly broken slabs may be too damaged to raise effectively, and a new layer is only as strong as its base

For a wider look at repair options, see this guide to repairing uneven concrete to learn about leveling, lifting, and resurfacing options. The Limits of Concrete Raising 

Concrete raising can lift a sunken slab, but it cannot solve every concrete problem. The slab’s condition and the soil beneath it both matter. Before choosing this repair, keep these limits in mind:

• Slabs that are badly cracked or broken may be too damaged to raise effectively.

• Raising levels the slab but doesn't fix poor soil, so a slab on ground that keeps moving can settle again.

• Done properly, raising shouldn't create new cracks. Existing cracks can still widen or narrow as the slab moves, and a slab that binds during lifting can crack.

• The drill holes are filled afterward but may stay visible.Not every uneven slab is a good fit for concrete raising. A closer look at the damage and the ground beneath it can help identify the right repair for your driveway. 

Before You Choose Concrete Raising or Resurfacing

Ask the estimator two things: is the slab still moving, and is the surface sound? The answers set the order of work. Then ask a few follow-ups. Are there voids under the slab, and how will they be filled? Will existing cracks be sealed after the lift? How visible will the filled drill holes be? Before agreeing to resurface a sunken slab, ask how the contractor will address any voids or movement beneath it.

At Lift It PRO, we ask homeowners to seal repaired seams, backfill exposed edges, and direct downspouts away from the slab after a foam lift. These steps are listed as warranty conditions in our FAQ, which also outlines the warranty terms, including which concrete qualifies. If you can't tell which problem you have, book a free estimate and have the slab checked before anything goes on top of it.