Basement cracks appear in two locations: the concrete slab underfoot and the interior face of the foundation wall. Both need attention before moisture and freeze-thaw cycles make them worse. We route and seal floor cracks with flexible material, inject interior wall cracks with polyurethane, and identify whether the crack is cosmetic or signals a deeper structural issue. When a crack points to foundation concerns, we refer it to the right specialist. Every visit includes a free assessment and a written quote.
Basement cracks originate from different causes depending on where they appear. Floor slab cracks typically stem from concrete shrinkage during curing or settlement of the base material beneath. These run vertically and allow water to migrate upward from below the slab. Wall cracks on the interior face usually indicate water or pressure working through from the exterior, often following a structural crack in the foundation itself.
Our approach matches the crack location. For floor slabs, we use a crack chaser to route the crack to a clean V-shaped or square profile, remove all dust and debris, then fill it with a flexible sealant that accommodates seasonal movement without re-opening. Interior wall cracks receive polyurethane injection through small ports drilled along the crack line, creating a bond that flexes with the concrete. This method mirrors foundation crack repair techniques but applied from inside the basement.
Some cracks signal structural movement that goes beyond a basement-side patch. When we identify that kind of crack, we recommend stepping up to the foundation repair service. We also pair crack sealing with interior waterproofing when active water is the root cause, ensuring the fix addresses both the symptom and the source.
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, noting whether it appears to be shrinkage, settlement, slab-only, or a through-crack from the exterior.
Route floor cracks to profile
Slab cracks are opened with a crack chaser to a consistent V or square shape, then vacuumed clean of all dust and loose material, leaving a dry channel ready for sealant.
Seal or inject based on location
Floor cracks receive flexible sealant pushed full-depth into the routed channel and finished flush with the surface. Wall cracks get polyurethane injected through ports spaced along the crack line.
Sealing a crack stops the leak at that point, but it does not address what caused the crack to form. A slab crack above an old plumbing trench will reappear unless the base is rebuilt. An interior wall crack weeping water will continue to weep until exterior drainage is corrected or the foundation is stabilized.
We repair the crack correctly the first time, but we also explain what is driving it. That honesty sometimes means recommending a second service, like pouring a new slab over a rebuilt base, or engaging foundation repair for structural issues. The quote reflects the full picture, not just the crack sealing.
Slab vs. wall cracks, sealing methods, injection, and when a crack signals bigger issues.
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 Pittsburgh 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.
Pittsburgh
★★★★★
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.
Aliquippa
★★★★★
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.
Mckeesport
★★★★★
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.
Monroeville
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Describe the cracks you see in your basement, whether in the floor slab or walls, and whether they are dry or actively weeping. We will assess them at no charge and provide a written repair quote.
