Most poured-concrete foundation cracks in West Chester homes are non-structural — they’re shrinkage cracks that formed as the concrete cured, and they show up years later as leak paths after the house settles or after a heavy rain. Good news: they’re fixable, often in a single half-day visit, with no excavation.
Crack injection — how it actually works
We inject the crack from the inside with one of two materials:
- Polyurethane (most common): flexible, expanding foam that fills the full depth of the crack including any voids on the outside. Best for active leaks because it works even when the crack is wet.
- Epoxy: rigid, structural bond. Used when there’s any concern about the crack being structural, or when the wall needs the strength back.
We drill small ports along the crack, surface-seal it with a fast-setting paste, then inject under pressure until the material comes out the other side of the wall. The seal extends through the full thickness of the foundation, not just a smear of caulk on the inside.
When a crack is NOT just a crack
Some cracks tell you something bigger is going on. We’ll flag it and recommend a structural engineer (not us, an actual engineer) if we see:
- Horizontal cracks across a wall — usually means soil pressure pushing the wall in
- Stair-step cracks in block walls that are getting wider
- Cracks wider than 1/4” with displacement (one side higher than the other)
- New cracks that weren’t there last year, especially near corners
We won’t sell you a $400 injection job if what you actually need is foundation reinforcement. Honest assessment first.
Block walls and stone foundations
The injection process above is for poured concrete. If you have a block wall or older stone foundation, the fix is different — usually a combination of interior waterproofing, parging, or a managed drainage solution. We work on all three foundation types common in Chester County homes.