What concrete leveling is
A slab sinks when the soil or base under it compresses, washes out or shrinks. The slab itself is usually still intact. Concrete leveling drills small holes, often about the size of a coin, through the low slab and injects material beneath it to fill the void and lift the slab. The holes are then patched.
The goal is a flat, continuous surface again: no trip edge at a sidewalk joint, no water pooling against the house, no driveway slab tilting toward the garage. Leveling fixes the symptom (the slab is low) and, if the cause is addressed, the problem too. If water keeps washing soil out from under the slab, the slab can settle again.
Mudjacking vs. polyurethane foam
Two methods are common. Mudjacking pumps a cement and soil slurry under the slab. Foam leveling injects expanding polyurethane. Contractors differ on which they use, and some offer both.
| Mudjacking | Polyurethane foam | |
|---|---|---|
| Material | Cement, soil or sand slurry | Expanding polyurethane |
| Weight added under slab | Heavier | Lighter |
| Typical cost (one contractor-type summary, low confidence) | About $300–$800 per 100 sq ft | About $2,000–$2,500 per 100 sq ft |
| Access holes | Larger | Smaller |
The per-100 sq ft figures above come from a single low-confidence national summary, so treat them as a rough comparison of the two methods and not as a quote. Ask each contractor what material they use, why, and what their repair carries for settling afterward.
Typical concrete leveling cost (national ranges)
Sacramento-specific leveling prices are not published in any source we could verify. These are typical national ranges. Local quotes will vary with slab size, how far it dropped, access, and the method used.
| Item | Typical national range |
|---|---|
| Mudjacking or slab leveling, per sq ft | $3–$8 |
| Typical single job | About $660–$1,900 |
| Average job (one source) | About $1,230 |
| Replacement alternative: removal | $2–$6 per sq ft (see concrete removal) |
| Replacement alternative: new plain driveway | $6–$12 per sq ft (see concrete driveways) |
Leveling usually costs less than replacing when the slab is in one solid piece. When most of the slab is cracked, or many slabs have dropped, the savings narrow and replacement may be the better value.
Why slabs settle in the Sacramento area
Sacramento County has widespread restrictive soil layers: cemented hardpan a few feet below the surface, claypans, and soil series (Redding and San Joaquin among them) that the county describes as having high shrink-swell potential. Clay swells when wet and shrinks as it dries, and that movement works on slabs and the base beneath them. Poor drainage, leaking irrigation or a downspout dumping beside a slab can speed up washout under it.
Tree roots lift slabs as well, which is a different problem, since leveling raises slabs and does not lower them. A lifted slab from roots usually needs the root issue handled before any concrete work. Sacramento's valley oaks and street trees are a common cause along sidewalks. Read concrete repair for the broader set of fixes.
When to replace instead of level
- The slab is cracked into many pieces, or the cracks are widening.
- The slab has dropped a lot in a short time, which can mean an active water leak or void.
- The surface is badly scaled or crumbling. See concrete resurfacing only if the slab is sound.
- The slab is part of an old driveway you want to redesign or widen. See driveway replacement.
A contractor can look at the slab, probe or sound it, and tell you which route fits. If the slab sits beside a public sidewalk, curb or driveway approach, work in the right-of-way may need a city or county encroachment permit. Confirm with your city or county before work starts.
Questions to ask a leveling contractor
- Which method will you use (mudjacking or foam), and why for this slab?
- Why did the slab drop, and what will you do about that cause, such as drainage, a leak or roots?
- How many and how large will the access holes be, and how are they patched?
- How level will the slab be at the end, and is there a risk of cracking during the lift?
- What happens if the slab settles again, and is that stated in writing?
- Is the price per square foot, per hole or per job?
Slabs that join a neighbor's property, a shared driveway approach or a public sidewalk can bring in other rules. If the work reaches the public right-of-way, a city or county encroachment permit may apply. In unincorporated Sacramento County, driveway approaches are handled by SacDOT.
How the referral works
Sacramento Crest Concrete does not level slabs and does not quote or contract. Submit a request with photos and the location of the sunken slab, and it passes your contact information to independent contractors who work in your area. A contractor can visit to measure and quote. You contract with and pay the contractor directly.
Verify the license at cslb.ca.gov before signing. California limits a home improvement down payment to $1,000 or 10 percent of the contract, whichever is less. Questions about how the process works are answered in the FAQ.
Main guide: concrete contractors in Sacramento.