Basement cracks start small and grow. We identify every crack in the slab and interior wall face, measure and classify each one, then seal or inject based on what the crack is and where it goes. Slab cracks get routed and filled with flexible sealant. Interior wall cracks get polyurethane injection through ports. When a crack signals something structural, we refer it to foundation repair rather than patch it. Free assessment, written quote.
Basement cracks live in two places. The slab on the floor cracks from shrinkage as concrete cures, from settlement under the slab, or from movement in the soil below. Wall cracks on the inside face of the foundation come from structural stress on the outside, water pressure, or frost heave pushing the wall inward. Each type behaves differently and needs a different repair approach.
Slab cracks are routed open with a concrete saw to create a clean channel, the debris is vacuumed out, and a flexible polyurethane or epoxy sealant is pushed into the full depth of the channel and finished flush. This allows the sealant to move slightly as the concrete expands and contracts with temperature. Interior wall cracks are injected with polyurethane resin through small ports drilled along the crack line. The resin flows into the crack, bonds the concrete, and flexes with seasonal movement, much like foundation crack repair but applied from inside the basement.
Some cracks are cosmetic and dry. Others are already weeping water or show signs of structural movement. We classify each crack during the assessment and recommend the right fix. If a crack is horizontal or shows signs of active pressure, we refer it to the foundation team rather than seal it from inside. If water is the issue, we pair the crack repair with interior waterproofing to stop the source.
Recent work
The repair sequence
How Basement Crack Repair Gets Done in Portland
Walk the basement and document
We inspect the entire basement, photograph every visible crack in the slab and walls, measure their length and width, and note whether they are wet or dry, straight or branching.
Classify each crack by type
Cracks are classified as shrinkage, settlement, structural, or water-driven. This classification determines the repair method and whether the crack needs a paired fix like drainage or foundation work.
Route slab cracks to profile
Slab cracks are cut open with a concrete saw to a clean V or square profile, vacuumed free of dust and loose material, and left dry and ready for sealant.
Seal or inject and cure
Slab cracks receive flexible sealant pushed full-depth into the routed channel. Wall cracks receive polyurethane injection through ports. Slab repairs cure in hours; wall injections cure overnight. Basement floor work follows if needed.
Cracks reveal underlying issues
Why Basement Cracks Matter Beyond the Crack Itself
A sealed crack is good, but only sealing it misses the reason the crack appeared. A slab crack above an old plumbing trench will reopen unless the base under the slab is rebuilt. A wall crack weeping water will keep weeping until the exterior drainage or the structural condition is fixed. We repair the crack correctly, but we also tell you what caused it and what the lasting solution is.
Sometimes that means a second visit to address the root cause. Sometimes it means pairing the crack repair with a new basement floor over a rebuilt base, or engaging the foundation repair team for structural work. The quote is honest about what the crack needs and what it will take to keep it from coming back. We also recommend maintenance steps to protect the repair.
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 Portland 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.
Portland
★★★★★
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.
Vancouver
★★★★★
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.
Gresham
★★★★★
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.
Hillsboro
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Describe the cracks you see in the basement, whether they are in the slab or walls, wet or dry, and we will visit free to assess them and provide a written quote for the repair work.
