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Cracked Foundation Blues

:( The house we bought 3 years ago has an unfinished basement which
I am making into a livable area. On the west wall is a large window which has a crack on each upper corner from the window to the top of the foundation. I have sealed the top of the foundation. When a heavy rain comes, these cracks leak quite profusely running down the wall and puddling on the floor. I have tried forcing expanding caulk into the outside to no avail. The cracks are very narrow. The top of the window inside is about 7ft. and the ceiling is 8ft. Outside the top of the window is 2ft from the patio which surrounds the window well. I could sure use some help.:confused:

Re: Cracked Foundation Blues

From your description it sounds like you may want to fix the cause of the cracks before fixing the cracks themselves or they will come back over time.

Is there a steel lintel or some kind of header system above the window? Can you post a picture of the inside and outside views?

Re: Cracked Foundation Blues

I agree with bp--this is very hard to visualize without some close-up photos or a drawn diagram to view what's going on.

These types of leaks can almost always be eventually stopped, so don't give up hope.

It may not seem apparent, but every residential window and door usually has a 3' strip of aluminum or vinyl called a "drip cap"; sometimes a small section of vinyl siding is used.

This deflects the rainwater coming down the side of the building above the window & prevents most of it from getting near the window.

Google "drip cap" window doors residential to see diagrams of how this works.

Basement & foundation windows are usually set in from the exterior so this type of window doesn't include a drip cap.

There are also waterproofing rubberized and concrete paints that may seal the exterior cracks & wall, but if the cracks are "active" (slowly expanding), as bp noted, the leaks can come back.

Re: Cracked Foundation Blues

Surface applied paints & coatings will fail over time, especially when applied from the interior. The cracks will still fill with water, so eventually (or sooner) thewater will find a new way past the paint coating.

We've had good results by hiring a company who does epoxy injection crack sealing. The entire crack is filled with an epoxy resin. It rarely costs more than a couple hundred dollars to repair one or two cracks.

Here's a description of the process.

Re: Cracked Foundation Blues
quicksilver wrote:

Outside the top of the window is 2ft from the patio which surrounds the window well.

Like JacktheShack and bp21901 mentioned without possibly pictures it's hard to determine any real answers also it's unclear if the foundation is poured concrete or blocks. It almost sounds like the patio is the source of where the water is coming from and getting in the cracks. Epoxy injection or hydraulic cement may be an option of closing the cracks.

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