I've been in my 1926 house for just over a year, and earlier this week I noticed water seeping in through the concrete wall behind my basement staircase after some intense rain. It was a small but steady trickle. The basement walls have been treated with what I assume is a water proof sealant although I do not know the exact details as it was done before I bought the house, but clearly it was done recently and they could not cover behind the staircase.
What are my options for sealing this up? So far I've only thought up:
- Rip the staircase out, use something like Drylok, rebuild the stairs
- Use closed cell spray foam and spray in the gaps (see 3rd photo)
There is no sump pump, and no additional water proofing that I know of. Outside is my driveway and the grading is relatively flat. (See last photo.)
The water came in just to the right of the window, behind the stringer, towards the back of the 5th step.
The missing riser was broken, so I just pulled it off. (Several of the others are also warped.)
There's gaps all along the edges of the stairs, and the stringer does not appear to be attached to the wall directly.
Blue arrow indicates where the water is coming in, roughly. The gutters deposit water far away from there though.