Homeowner decision guideU.S. national guidance

evaluate options

Reviewed and updated September 22, 2026

What are the options for a sunken concrete slab?

Safety boundaryDo not stand on a visibly unstable slab, force movement with a load or drill injection holes yourself. Slab lifting is specialized work, and concrete drilling creates a silica-dust hazard.

For a sunken ground-supported slab, first evaluate why it settled and whether the existing concrete remains suitable to retain. Professional slab lifting may be an option for some slabs, while replacement or other site work may be more appropriate where the concrete is badly damaged or support conditions remain unresolved. A top-surface patch does not establish that lost support has been restored.

Ask for the target elevation, drainage result and limitations of the proposed correction. Restoring the height alone does not necessarily correct poor underlying soil or an ongoing water problem. A patio also needs to fit adjacent doors, steps and occupied spaces. If the concern involves a structural slab or foundation rather than ordinary flatwork, obtain the appropriate structural assessment before selecting a lifting service.

Separate condition, intended use and project scope

Which situation best matches the project?

The slab is reasonably intact but below the intended position

A lifting assessment can consider whether the slab can be raised and adequately supported at the intended position. Ask what caused the settlement and what the proposal does about that cause. A successful elevation change is not proof that every underlying soil condition has been corrected. Discuss visible repair holes, existing cracks and the possibility that the desired movement cannot be achieved as planned.

Notice next: Request a written target and an explanation of residual risks before comparing material or price claims.

The concrete is extensively damaged or settlement is continuing

Compare replacement and support preparation with a lifting proposal rather than assuming the existing slab must be saved. The relevant questions include whether it can move as intended, whether damage limits its usefulness and whether the underlying problem remains active. Ask each bidder to explain what happens if the slab cannot be corrected within the proposed scope.

Notice next: Use a condition map and previous repair history to obtain comparable alternatives. Have the estimate separate slab work from any necessary drainage or ground correction.

A patio has settled beside the house or an outdoor structure

Evaluate the finished patio relationship to doors, steps, posts and water movement. A height correction that fixes one edge can leave another transition or drainage question unresolved. Clarify whether anything attached to or supported by the patio changes the assessment. The intended use of the space matters as much as making the panel appear level in one photograph.

Notice next: Provide a wide view and identify any supported feature or building symptom. Ask for the final elevations and drainage objective to be coordinated before work.

Safe observation

What to record before contacting a professional

Use only safe, non-destructive observations and existing records. Do not create access or disturb a hazard to complete this list.

These observations organize a conversation; they do not diagnose the property or prove service availability.

What to record

Photograph the settled slab and all adjacent transitions from safe access points.
Record the history of settlement and any earlier lifting or replacement work.
Observe ordinary rainwater paths and collect drainage or utility records relevant to the area.
List doors, steps, posts, walls and other features connected to or immediately beside the slab.

Stop and get appropriate help

Stop routine repair planning when the slab’s structural role or building movement is unresolved.
Resolve buried structures and utility concerns before ground disturbance or a proposed injection operation.

Move from information to action

Who is the useful next contact?

Concrete lifting or repair professional

Use this contact to assess slab condition, lifting feasibility and the proposed support correction. Ask what the work cannot resolve.

Why did this slab settle, and is that process still active?
What target elevation and drainage result are included?
How will the proposal address support rather than only height?
What is the plan if the existing slab cannot be lifted as intended?

Concrete replacement contractor

Use a replacement estimate as a meaningful alternative when existing damage or support conditions may limit lifting. Compare preparation and final use, not just the slab area.

Why did this slab settle, and is that process still active?
What target elevation and drainage result are included?
How will the proposal address support rather than only height?
What is the plan if the existing slab cannot be lifted as intended?

Drainage or structural professional when indicated

Use drainage expertise for water-related conditions and structural assessment when the slab supports or interacts with the building in a way ordinary flatwork repair does not address.

Why did this slab settle, and is that process still active?
What target elevation and drainage result are included?
How will the proposal address support rather than only height?
What is the plan if the existing slab cannot be lifted as intended?

Contact guidance explains who may help and what to prepare. It does not verify a provider, price, license, arrival time or acceptance of this request.

Professional help

Use this guide to prepare for a qualified local professional.

The available connection is limited to eligible new concrete projects. This guide remains available for decision support without presenting an ineligible phone route.

Repair-only concrete work is not connected by this line

Check licensing, service area, schedule, scope and written estimate directly with professionals you consider.

Short answers

Questions people ask before the call

Does lifting permanently fix poor soil?

Not automatically. ACI guidance distinguishes raising the slab from correcting underlying poor soil conditions. Ask what remains and how it affects recurrence.

Can all cracked slabs be lifted?

Suitability depends on condition and the intended correction. Ask the assessor to compare retaining the slab with removal and replacement rather than promising a universal result.

Will the repair holes be invisible?

Do not assume that. Discuss the expected finished appearance and any separate surface treatment before accepting the work.

Where this guidance applies

The explanation, safe observations and comparison questions apply as general U.S. homeowner guidance.

Permits, adopted codes, licensing, property responsibility and provider availability must be confirmed for the actual location and scope.

A ZIP code can help screen service availability; it does not establish a local fact, price, permit rule or provider commitment.

Sources and boundaries

What supports this guide?

National Ready Mixed Concrete Association — CIP 14 — Finishing Concrete FlatworkFinish should suit the use; exterior surfaces need drainage and suitable wet traction; broom texture differs from a smooth troweled finish. Boundary: Qualitative concrete-material guidance, not an adopted local code, structural design, mix order, repair warranty or property diagnosis. No numerical specifications or use schedules are imported. Scope: national. Source checked 2026-09-22.
National Ready Mixed Concrete Association — CIP 23 — DiscolorationMaterials, finishing and curing can affect concrete color; color alone does not identify every cause or establish structural condition. Boundary: Qualitative concrete-material guidance, not an adopted local code, structural design, mix order, repair warranty or property diagnosis. No numerical specifications or use schedules are imported. External oil, irrigation and corrosion stains are explicitly outside the main discoloration scope. Scope: national. Source checked 2026-09-22.
National Ready Mixed Concrete Association — CIP 4 — Cracking Concrete SurfacesCracking has multiple mechanisms including shrinkage, restraint, support problems and environmental effects; appearance alone does not prove a cause. Boundary: Qualitative concrete-material guidance, not an adopted local code, structural design, mix order, repair warranty or property diagnosis. No numerical specifications or use schedules are imported. Scope: national. Source checked 2026-09-22.
American Concrete Institute — Concrete Repair Application Procedures: Slabjacking (RAP-11)Slabjacking raises settled slabs by controlled injection under them; suitability depends on slab condition, underlying support and the intended correction. Boundary: No residential success rate, price comparison, universal tolerance or site suitability is established. Scope: national. Source checked 2026-09-22.
Common Ground Alliance / 811 Before You Dig — 811 Before You DigArrange utility-location notification before ground disturbance; do not rely on old assumptions about buried facilities. Boundary: State notice periods, ticket duration, mark tolerance and private-line arrangements must be verified locally; no digits are presented as a call path. Scope: national. Source checked 2026-09-22.
CDC / National Institute for Occupational Safety and Health — Silica and Worker Health | Silica | CDCCutting, drilling and grinding concrete can create hazardous respirable silica dust; professional exposure controls are needed. Boundary: This is hazard guidance, not a household exposure measurement, medical diagnosis or complete contractor control plan. Scope: national. Source checked 2026-09-22.
University of Minnesota Extension — Moisture in basements: causes and solutions — University of Minnesota ExtensionWater directed toward a foundation and concentrated roof runoff can contribute to moisture problems; investigate water source and drainage. Boundary: No source-specific grading dimension or drainage system design is made a national code. Water intrusion is not automatically a foundation failure. Scope: state. Source checked 2026-09-22.

No slab is approved for lifting or replacement without site assessment.

Subsurface conditions and future movement remain uncertain.

No price, traffic-opening time, lift amount or service-life guarantee is supplied.