Cracked, lifted or sunken concrete around Sacramento can often be lifted with slurry or foam, ground down, sealed, patched or resurfaced. Root-heaved and badly broken panels are usually replaced. Any repair should also fix the cause, such as sprinklers soaking slab edges or water trapped over hardpan, and foundation cracks warrant a structural evaluation.
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Not every cracked or uneven slab has to be torn out. Depending on the cause, concrete can often be lifted, ground, sealed, patched or resurfaced for less disruption than a full replacement. The key is figuring out why it failed, because a repair that ignores the cause usually fails again.
Why concrete moves around Sacramento
- Shrink-swell clay. Many valley soils are heavy clays that crack open in the dry season and swell when the rains return. Uneven moisture under a slab means uneven support.
- Hardpan and trapped water. Parts of the region have a cemented hardpan layer a few feet down. Water that gets under a slab may sit there and soften the soil instead of draining.
- Irrigation. Sprinklers that hit slab edges every summer keep one side wet while the rest dries, a common cause of tilting walks and patios.
- Tree roots. Large street and yard trees lift sidewalks, driveway edges and patio corners.
- Settling fill. Backfill near foundations and garages in newer subdivisions can compress over time.
- Hot-weather shrinkage. Concrete that dried too quickly or has joints too far apart cracks more.
Repair options
- Slab lifting (mudjacking): a cement-based slurry is pumped under a sunken slab through drilled holes to raise it and fill voids.
- Polyurethane foam lifting: expanding foam injected through smaller holes. It's lightweight and cures quickly.
- Grinding: a raised edge, often from roots, can be ground down to remove a trip hazard.
- Crack and joint sealing: flexible sealants keep water out of the base.
- Patching and resurfacing: repair mortars or thin overlays can renew a worn but sound surface.
- Section replacement: badly broken or root-heaved panels are cut out at joints and repoured.
When lifting makes sense
Lifting works best when the slab is mostly intact, has sunk as a unit, and the cause has been dealt with. It can't fix a panel that was pushed up by a root; that usually means grinding or replacement. Fixing the water source, such as moving sprinkler heads, extending downspouts or improving grade, should be part of the plan.
Sidewalk notices and trip hazards
In the City of Sacramento, the property owner is responsible for repairing the public sidewalk next to their property, and the city's handbook describes vertical displacement of half an inch or more as one sign of a defective sidewalk. If you've received a repair notice, the work has to meet city specifications and the inspector should be contacted before work begins. Other cities and the county have their own rules and permits. See our guide to sidewalk repair notices.
When it might be structural
Cracks in a patio or garage floor are usually not structural. But cracks in foundation walls, slabs under the house, stair-step cracks in brick or stucco, or doors and windows that suddenly stick can point to foundation movement. In those cases, start with a structural engineer or foundation specialist. That work involves permits and licensed contractors.
Questions to ask
- What caused the problem, and how will the repair address it?
- Will you lift, grind, patch or replace, and why?
- How will the drill holes or ground areas look afterward?
- Is there a warranty if a lifted slab settles again, and what is your CSLB license number?
Have a trip hazard? Mark your request as urgent and request a concrete repair contractor. Not sure which way to go? Read what drives driveway cost for when replacement is worth pricing.
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Frequently asked questions
Is mudjacking or foam lifting better?
Both can lift sunken slabs. Cement-based slurry is a long-established method; polyurethane foam uses smaller holes, is lighter and cures quickly. The right choice depends on the slab, the voids beneath it and the contractor's experience.
Why are my walkway and patio tilting?
Around Sacramento, common causes are clay soil drying and swelling unevenly, sprinklers keeping one edge wet, tree roots, and loose fill near the house. A contractor should identify the cause before recommending lifting or replacement.
Are cracks in my driveway a structural problem?
Usually not. Shrinkage cracks in flatwork are common. Cracks in foundation walls, stair-step cracks in stucco or brick, or sticking doors and windows can point to foundation movement and are worth a structural engineer's look.
Sources and further reading
- Contractors State License Board (CSLB): C-8 Concrete classification
- CSLB: minor work exemption rises to $1,000 (AB 2622), effective January 1, 2025
- City of Sacramento: Sidewalk Maintenance Program Handbook
- City of Sacramento Public Works: Engineering Services Permits
- Sacramento County Department of Transportation: Encroachment Permits
- City of Elk Grove: Encroachment Permits
- City of Roseville: Engineering Permits
- City of Davis: Encroachment Permits
- UC Master Gardeners of Sacramento County: Soil (clay and hardpan resources)
- USDA NRCS Official Soil Series: San Joaquin (clay over duripan)
- California Department of Water Resources: Model Water Efficient Landscape Ordinance
- USA North 811: call before you dig in Northern California
- American Concrete Institute (ACI)
- Portland Cement Association (PCA)