Sunken or Heaved Concrete in Ottawa: Lift, Patch or Replace?
Too few published prices for lifting or partial replacement
The lifting and partial-replacement prices we found come from one vendor. Full replacement uses the published new-concrete ranges.
Reviewed 2026-09-30 · how we set these ranges
Concrete that moves up or down is telling you something about what is under it. Pick what you see to get the checks and the repair routes to ask about. Resurfacing will not fix movement that comes from below.
What are you seeing?
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A section has sunk
- What the sources say
- The Code's appendix says draw-down of water by fast-growing trees can decrease the volume of soil supporting floors-on-ground, causing settling.
- Have a contractor check
- How far it has dropped, and what is under it.
- Repair routes to ask about
- Lifting (also called mudjacking or slab jacking), partial replacement, or full replacement.
- When replacement comes up
- Ask how each route deals with the cause.
- Published price
- Too few published prices for lifting; new broom-finish concrete runs about $9 to $15 per sq ft.
-
A section has lifted or heaved
- What the sources say
- Clays, silts and very fine sands support ice lenses; sands and gravels do not (NRC Digest 182).
- Have a contractor check
- Whether it moves with the seasons, and the soil and base under it.
- Repair routes to ask about
- Partial or full replacement with the base dealt with.
- When replacement comes up
- An overlay will not stop movement from below.
- Published price
- Too few published prices for partial replacement.
-
Steps pulling away from the house
- What the sources say
- The Code requires concrete stairs with more than 2 risers to sit on walls or piers to foundation depth, or be cantilevered from a foundation wall at least 200 mm thick.
- Have a contractor check
- How many risers, and how the steps are supported now. Keep off them if they move underfoot.
- Repair routes to ask about
- Rebuild on proper support, or repair if the support is sound.
- When replacement comes up
- Rebuilt steps that provide access to a building may need a permit; ask the City.
- Published price
- Poured sets of 3 to 5 steps run about $2,500 to $5,000+ (Ontario published prices).
-
Slab tilts toward the house
- What the sources say
- An attached garage floor must slope to drain liquids to the outdoors under the Code; we found no Code slope for a patio.
- Have a contractor check
- Where water goes now, and whether the slab is still moving.
- Repair routes to ask about
- Lifting, partial or full replacement.
- When replacement comes up
- Ask the contractor to put the planned slope in writing.
- Published price
- Too few published prices for lifting.
Not a diagnosis: a contractor has to see the concrete. Every number above is a published figure or a City or Code rule.
The rules behind this job
Draw-down of water by fast-growing trees can decrease the volume of soil supporting foundations and floors-on-ground, thus causing settling.
O. Reg. 163/24, Note A-9.4.4.4(1)Exterior concrete stairs with more than 2 risers and 2 treads are supported on concrete or masonry walls or piers at least 150 mm across, or cantilevered from the main foundation wall.
O. Reg. 163/24, Div. B, 9.8.9.2Whoever digs is an excavator under Ontario's Underground Infrastructure Notification System Act, 2012 and must not dig until a locate request has been submitted and the utilities have responded. Locates are free; submit the request through Ontario Dig Authority at least 5 business days before digging.
Ontario Underground Infrastructure Notification System Act, 2012; Ontario Dig AuthoritySince March 1, 2026 the City of Ottawa has required a hardscaping contractor licence for businesses that install or alter concrete pads, patios, walkways, steps, driveways and retaining walls on private property. Licence holders must carry at least $2,000,000 of commercial general liability insurance and give clients the City's Landscaping Education Guide. Ask to see the licence and check the City's list yourself; we do not check it. The Licensing By-law excludes "minor repairs or minor alterations", which it does not define; ask the City whether your repair counts.
City of Ottawa, Hardscaping Contractor Licence; Licensing By-law 2002-189 (By-law 2026-222)
Ask before you sign
- What is causing the movement, and how does your repair deal with it?
- Who will submit the locate if anything is dug?
- What happens if the base needs more work than the quote assumed?
More on this work: Concrete Repair
Quick answers
Can heaved concrete be resurfaced level?
No: an overlay goes on the slab as it is, and the movement comes from below. Ask about lifting, partial replacement or full replacement.
Want this done at your place?
Tell us about your concrete job and we'll send it to local Ottawa concrete contractors, who reply by email. We send it out to local contractors for you. Free, no pressure.