Fixing Out-of-Tolerance Slabs with Self-Leveling Concrete
A commercial slab that doesn't meet the flatness spec for your finish flooring becomes a problem for the tile, plank or polish installer. Self-leveling concrete is the solution. Laval Concrete applies a bonded underlayment over the existing slab to bring it to the target tolerance, ready for any finish. The slab gets corrected without tear-out, in days instead of weeks. Every project includes a free written estimate.
Most Finish-Flooring Failures Start with the Slab Itself
Tile lippage, plank gaps, coating inconsistency, polished-floor streaking, these are often blamed on the finish installer when the root cause is a slab poured outside the flatness tolerance for that finish. No finish installer can make a wavy slab look flat. The slab has to be flat first.
Self-leveling concrete fixes the slab before the finish goes on. We diamond-grind the existing concrete to expose a clean surface, apply a bonded primer, pour the self-leveling underlayment to the target depth, and let it cure to the finish-flooring's tolerance. The result is a slab that meets spec, which makes the rest of the install succeed.
We measure the existing slab across the entire floor area, identify high and low spots, calculate the depth needed to reach the finish-flooring's tolerance, and confirm the plan with the finish-floor contractor before we start.
Grind and prime
The slab is diamond-ground to remove contaminants and old coatings, exposing clean concrete. A bonded primer matched to the self-leveling system is applied to ensure full adhesion between the new pour and the existing slab.
Mix and pour
The self-leveling material is mixed to the manufacturer's water ratio, poured to the calculated depth, and gauge-raked to distribute it evenly. The material self-levels to a flat plane within minutes of placement.
Cure and handoff
The pour cures on the manufacturer's schedule. Once cured, the slab is verified against the finish-flooring's tolerance spec and handed to the finish installer ready for tile, plank, polish or coating.
Coordination matters
Self-Leveling Works Best When Scheduled with the Finish Trade
Self-leveling concrete is most effective when planned into the build sequence with the finish-flooring contractor, not added as an emergency fix. We coordinate the target tolerance, the pour depth, and the cure timeline with the tile, plank or polish installer from the start.
On larger projects, we also coordinate with adjacent commercial floor repair work, anti-slip flooring in other zones, and any structural issues that need to be addressed before the self-leveling pour. This sequencing prevents delays and ensures the finish installer gets a slab that's ready to work with.
Tolerance specs, primer systems, depth ranges and when to self-level before finishing.
Each finish has its own tolerance, large-format tile is more demanding than plank, polished concrete more than tile. The finish installer's spec defines the target; we pour self-leveling to meet that target, and we will get the spec from your finish-flooring trade up front.
Yes, modern self-leveling systems can be poured at a thin overlay depth for minor tolerance corrections, up to several inches for major fixes. The system spec changes with depth; we use the right one for the pour.
Always. The primer is what bonds the new pour to the existing slab; without it, the self-leveling delaminates over time. We use the manufacturer-matched primer for the system, applied to a diamond-ground substrate.
Foot traffic typically within hours, but finish flooring usually waits longer for the pour to cure and dry. We give the finish-flooring trade the cure timeline so they can schedule their install.
Cost and disruption. A self-leveling overlay corrects the existing slab without tear-out, in a fraction of the time and budget. Where the existing slab is structurally failing rather than just out-of-tolerance, a new slab is the right call; we will tell you which case yours is.
Client reviews
What Laval Operations Say About Their Self-Leveling Pours
Tile contractor had refused to install on our out-of-tolerance slab. Self-leveling pour brought it to spec inside three days; tile install went perfectly after that. Fixed the actual problem.
W. V.
Construction Manager, Laval
★★★★★
Coordinated with our polished-concrete trade from day one. Target tolerance agreed, pour hit it, polish came out flawless. Real trade coordination, not just a contractor.
Z. V.
Retail Build-Out Director, Montreal
★★★★★
Existing slab had two inches of variation across the floor. Self-leveling brought it flat, finish coating installer was thrilled. Cost a fraction of a new slab pour.
Y. V.
Property Manager, Terrebonne
★★★★★
They were honest that part of our slab needed structural repair, not just self-leveling. Did both in sequence. The honesty was worth the slightly bigger scope.
Q. X.
Healthcare Facility Director, Longueuil
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Tell us the floor area, the target finish flooring and its tolerance spec, and we will assess the existing slab and quote the self-leveling pour in writing.
