Cracks in a basement happen in two places, the slab on the floor and the inside face of the foundation wall. Oshawa Concrete fixes both, routing and sealing slab cracks before water and freeze-thaw work them open, and injecting interior-face wall cracks to stop them from weeping. When a crack is more than cosmetic, we route it up to foundation crack repair on the engineered side. Every assessment is free and the quote is written.
A basement crack might be in the slab on the floor or in the inside face of the foundation wall. The two look different, behave different and get fixed different. Slab cracks usually come from shrinkage or settlement under the slab, run vertically, and let water move from below into the basement. Wall cracks on the inside face come through from the outside, usually because the structural crack in the foundation wall lets water work through.
We assess both, classify each, and pick the right repair. Slab cracks get routed to a clean profile, cleaned out, and sealed with a flexible material that can handle the small movements that come back as the seasons change. Interior wall cracks get injected with polyurethane that bonds and flexes, similar to foundation crack repair but applied from inside.
Where the crack is structural, we say so. That kind of crack belongs to the wider foundation service, and we will refer it up rather than paper over it with a basement-side patch. Cracks tied to active water get paired with interior waterproofing to address the cause.
Recent work
How it works
How We Repair Basement Cracks in Oshawa
Survey every basement crack
We survey every crack we can see in the slab and along the inside face of the wall, photograph and measure each, and classify them as shrinkage, settlement, slab-only, or telegraphing from the outside of the wall.
Route slab cracks open
Slab cracks are routed open with a crack chaser to a clean V or square profile, the dust and any loose material is blown clear, and the channel is left dry and ready for sealant.
Seal or inject by type
Slab cracks get a flexible sealant pushed full-depth into the routed channel and finished flush; interior-face wall cracks get polyurethane injection through ports drilled into the wall along the crack.
Monitor and pair with cause
The repaired cracks are checked after curing, and where the cause is active water, we pair with interior waterproofing; where it is structural, we refer to foundation crack repair.
Basement cracks have a cause
Basement Cracks Are Symptoms, Not Just Cracks
Sealing a basement crack matters, but only sealing it leaves the cause to come back. Slab cracks above an old plumbing trench keep cracking until the underlying base is rebuilt. Interior wall cracks weeping water keep weeping until the outside drainage is fixed.
We do the crack repair right, but we also say what is causing each one and what the lasting fix is. Sometimes that means another visit, sometimes a paired upgrade like a fresh slab over a rebuilt base, sometimes engaging the foundation repair side. The quote is honest about it.
Slab vs wall cracks, sealing, injection, and when a basement crack means 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 Oshawa Homeowners Say About Their 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.
Oshawa
★★★★★
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.
Toronto
★★★★★
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.
Mississauga
★★★★★
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.
Brampton
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Tell us about the cracks you are seeing in the basement, slab or walls, dry or weeping, and we will assess them free and put any crack repair work into a written quote.
