We moved into our house about a year ago and quickly found that we have a leaking issue into our basement. The slab near our basement window has sunken so the water pools up against the house on big rain storms and eventually seeps in. I have sealed the crack along this problem area twice, which has slowed the issue but it still leaks. Jacking is not an option for several reasons. We had several contractors give us that opinion. We could tear up the concrete and have someone pour new slabs that are graded away, but we are well under any concrete contractor's minimum. We know this would solve the problem, hopefully, but we would be looking at spending around $1,500 to meet their minimums.

My question is, can I use hydraulic water-stop cement to build a better seal between my sidewalk and foundation? We are looking for a solution that won't break our bank and at least get us through the winter since this is only an issue with big rain storms and doesn't leak with minor storms.

The wet area is where we had a towel that lays there to stop the leaking. The water pools from the stair corner to the edge of the window. The water is not flowing up and over the window sail.

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    Hydraulic cement may help if it does then the pool area gets larger and goes in at the window or the next expansion crack in the sidewalk. Just moving the wet spot around. Getting the sidewalk fixed so it drains away from the house may save more in the long run if it is a finished basement.
    – Ed Beal
    Sep 14, 2016 at 13:26
  • Where is the water entering the basement? Is the entire foundation wall weeping, or is there a crack (or gap at the basement floor)? Sealing the inside crack(s) is far likely to succeed than just creating a birdbath on the outside. Sep 14, 2016 at 19:30
  • @CarlWitthoft - I have not removed all of the drywall from ceiling to the floor in the basement. From what I can tell the wet area is about 5 inches wide and originate from the corner of the window basically. The entire wall is not weeping. Using the sealant has already drastically slowed the leak and it only leaks when the water really pools up on the outside. I was trying to avoid replacing drywall, but I don't know if attacking it from the inside makes more sense at this point.
    – junta
    Sep 14, 2016 at 23:06
  • Sounds more like a leak between windowframe and foundation wall. Sep 15, 2016 at 12:30
  • If that is the case, would there be another option to solve the leak?
    – junta
    Sep 16, 2016 at 3:20

1 Answer 1


Indeed, hydraulic water-stop cement can fix your leak.

With that said I strongly advise 2 things. Finding out the actually cause (ie. foundation sinking or separating) and remove all the sealer you currently have, so the product adheres to the concrete and stucco properly.

Quickrete's claim: QUIKRETE® Hydraulic Water-Stop Cement will block running water when application is made to masonry or concrete surfaces. This special formulation allows the product to obtain high strength and rapid setting while repelling water. QUIKRETE® Hydraulic Water-Stop Cement solves leakage problems wherever active water is present, in all masonry and concrete above and below grade.

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    Note that hydraulic cement expands somewhat as it cures, so for the best seal you may actually want to chisel the crack a bit wider to pack cement deeper into it. I believe there are articles and videos on the This Old House website, and elsewhere which describe this in more detail.
    – keshlam
    Sep 14, 2016 at 12:00
  • But a gap between exterior slabs and the foundation wall doesn't allow water into the basement. Something else is wrong. Sep 14, 2016 at 19:31

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