About 8 out of every 10 Akron basements we quote need interior waterproofing. Not because it is cheaper for us, but because in most of these houses the wall is sound and the drainage around it is not.
That said, there are 4 situations where interior work is the wrong answer and digging is the only real fix. This page covers both sides so you can tell which one you are looking at.
Side by side
| Interior | Exterior | |
|---|---|---|
| What it does | Relieves the pressure under your floor | Re-seals the wall from the water side |
| Time on site | 2 to 4 days | 5 to 10 days |
| Season | Any, frozen ground included | Not winter |
| Your yard | Untouched | Plants and walkways come up |
| Akron price | $68 to $92 per linear foot | Roughly 3x that |
| Warranty | Lifetime, transferable | Lifetime, transferable |
How interior waterproofing actually works
A channel is cut around the inside edge of the slab. Slotted pipe goes in clean stone, runs the perimeter, and feeds a sump pump . A wall barrier sends any seepage down into that channel instead of onto your floor.
The point is not to stop water. It is to give water a route that is easier than pushing through concrete. That is why paint fails and drainage does not.
How exterior waterproofing actually works
The ground is dug to the footing along the affected side, usually 7 to 9 feet (2.1 to 2.7 m) down. The wall gets cleaned and patched, then a membrane and a dimpled drain board go on the outside face. A new footing drain is laid, and the trench is backfilled with stone rather than the clay that came out.
It is the same specification a new build should get, which is why doing it during construction costs so much less.
The 4 times exterior is the right call
- The wall itself is failing. Old stone or early block losing mortar from the outside face. You cannot fix the outside of a wall from the inside.
- The original clay tile drain has collapsed. Nothing is relieving the footing, and an interior system alone leaves the wall sitting in water.
- The wall has moved. A bow or a sideways crack is structural and often gets held and re-waterproofed together.
- You are already digging. New driveway, addition or landscaping. The trench is the expensive part, so use it.
The question that decides it
Where does the water arrive?
- At the floor line, or up through the slab. Pressure from below. Interior drainage.
- Through the face of the wall, mid height, over a wide area. The wall is porous or the outside seal has failed. Exterior.
- At one point, always the same spot. Neither. That is a crack, and it gets injected .
A contractor who only sells one of these will always find a reason you need that one. We quote both and put the reasoning in writing next to the price. The full method list covers the other 4 options if neither of these fits what you are seeing.
