How We Repair a Leaking Foundation Crack
A leaking crack doesn't get better on its own. Here's exactly how our crew fixes one from the inside — not by covering it up, but by rebuilding the wall around it.
What you just watched, step by step
Every interior crack repair follows the same sequence. The order matters — each step is what makes the next one hold.
Locate the leak
We inspect the inside of the foundation wall and find the exact crack where water is getting in, then mark out the repair area along the full length of the crack.
Cut along the repair area
Using a grinder with a masonry blade, we cut carefully along both sides of the marked crack. This creates a controlled repair channel — the crack is opened up, not painted over.
Chisel out the concrete
With a hammer and masonry chisel we remove the concrete between the cuts, opening the channel wider and deeper than the original crack. That lets the repair material bond to solid, sound concrete instead of a weak surface. All loose concrete, dust and debris is removed.
Prepare the area
The open channel is thoroughly cleaned and prepared to the waterproofing product's requirements — including dampening the concrete when the product calls for it.
Apply crystalline waterproofing
A cementitious crystalline waterproofing material is applied directly onto the prepared concrete inside the channel and worked thoroughly against the surface, so it bonds inside the concrete rather than sitting on top of it.
Rebuild and seal
The channel is packed with a compatible waterproof repair mortar or hydraulic repair material, compacted firmly so there are no voids anywhere in the repair.
Finish
The repair is smoothed flush with the surrounding wall, and any final waterproofing coat the system calls for is applied.
A repair zone — not a patch
When we're done, the original crack sits inside a properly prepared, bonded and waterproofed repair zone. That's the difference between a fix that lasts and one you'll be looking at again next spring.
- Repair material bonded to solid, sound concrete — not a weak surface
- Waterproofing worked into the concrete inside the channel, not painted over the top
- Channel packed and compacted with no voids, finished flush with the wall
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