Basement cracks appear in two locations: the floor slab and the interior wall face. Both need attention before freeze-thaw cycles or water pressure make them worse. Gatineau Concrete routes slab cracks to a clean profile and seals them with flexible material, while interior wall cracks receive polyurethane injection through strategically placed ports. When a crack signals a deeper structural issue, we escalate to foundation repair specialists. Every assessment is free, and your quote is in writing.
The slab and the wall are different concrete elements with different failure modes. A slab crack typically stems from shrinkage during curing or settlement of the base underneath. These cracks run vertically and allow water to migrate upward from below. Wall cracks on the interior face originate from structural movement or external water pressure working through from outside.
Our approach matches the crack type. Slab cracks are routed open with a crack chaser to expose a clean V or square channel, then filled with a flexible sealant that accommodates seasonal movement without re-opening. Interior wall cracks are sealed using polyurethane injection through small ports drilled along the crack line, creating a bond that flexes with the concrete. This method mirrors the approach used in foundation crack repair but applied from the inside.
Some cracks point to bigger problems. Horizontal wall cracks often indicate soil pressure pushing inward, which requires structural foundation work rather than a cosmetic seal. Wet cracks paired with active water entry need interior waterproofing to address the root cause. We identify these situations and refer them appropriately rather than masking the symptom.
Recent work
The repair sequence
Step-by-Step Basement Crack Repair Process
Document and classify each crack
We photograph, measure, and categorize every visible crack in the slab and along the interior wall surface. Classification determines whether the crack is cosmetic shrinkage, settlement-related, or structural in nature.
Route slab cracks to clean edges
Using a crack chaser, we open slab cracks to a uniform V or square profile, remove all dust and loose material with compressed air, and prepare the channel for sealant application.
Seal or inject based on location
Slab cracks receive flexible sealant pushed to full depth and finished flush with the surface. Wall cracks get polyurethane injected through ports spaced along the crack, creating a continuous bond.
Assess cause and pair with solutions
After curing, we evaluate what caused each crack. Active water issues get paired with interior waterproofing; structural concerns get referred to foundation crack repair specialists.
Cracks reveal underlying issues
Why Sealing Cracks Alone Is Not Enough
A sealed crack stops water at that point, but if the underlying cause remains, the crack or a new one nearby will return. A slab crack above an old plumbing trench will re-open unless the base is rebuilt. An interior wall crack weeping water will continue to weep until exterior drainage is corrected or the wall is stabilized.
We seal the crack properly, but we also identify and communicate the root cause. Sometimes that means a follow-up project like pouring a new slab over a rebuilt base. Sometimes it means engaging foundation repair for structural underpinning. The quote is transparent about what the lasting fix requires and what the timeline looks like.
Slab vs wall cracks, sealing methods, injection, and when a crack signals something bigger.
Yes. Slab cracks get routed to a clean profile and sealed with a flexible material that handles small seasonal movement. Wall cracks on the inside face get polyurethane injected through ports along the crack. The repair matches the crack.
Not always. Some are dry hairlines that are cosmetic for now but worth sealing before water finds them. Others are already wet and need the cause addressed, drainage, an exterior crack, or a structural issue, alongside the crack repair itself.
Yes. Horizontal cracks usually mean soil pressure is pushing the wall and the right answer is structural; we refer those to foundation crack repair on the engineered side rather than injecting from inside.
It will stop the leak at that specific crack. If the basement is wet in multiple places, the root issue is usually drainage rather than the cracks themselves; the right answer is also interior waterproofing to address the cause.
Most basement crack visits are a few hours to a full day, depending on how many cracks and whether they are slab or wall. The slab repairs cure within hours; injected wall cracks cure overnight. The timeline is on the quote.
Homeowner reviews
What Gatineau Homeowners Say About Basement Crack Repairs
Slab crack above an old plumbing trench got routed and sealed properly, and they said up front the base under it was the real cause. Honest call, the crack stayed sealed.
Q. B.
Gatineau
★★★★★
Three slab cracks and one interior wall crack all in one visit. They classified each, repaired each the right way, and the basement is dry through the season.
X. K.
Ottawa
★★★★★
They flagged my horizontal wall crack as structural and referred it up rather than just injecting. Could have charged me and walked away. Glad they did the right thing.
Z. E.
Nepean
★★★★★
Routed slab cracks instead of just smearing sealer on top like the last guy did. The repair has held through two springs of melt. Real method, real results.
F. V.
Barrhaven
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Describe the cracks you see in your basement, whether they are in the slab or walls, dry or actively weeping, and we will visit to assess them free and provide a written repair quote.
