How to fix a little wet part in the basement insulation?

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Posted by: from Mississauga
9/28/2015 at 1:52:28 PM

Under only one of the unfinished basement windows in the lower edge of the insulation occurs a little wet line on this insulation (like 3 meters wet line). And in August, I saw a couple of liquid drops on the wall and ground. Can you tell me what is the cause and how to fix it please?

How to fix a little wet part in the basement insulation?
How to fix a little wet part in the basement insulation?
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Date/Time9/28/2015 at 7:59:56 PM


Cut the plastic and insulation up to the window. The window may be leaking or one of the form bolt holes maybe leaking. That is the easiest way to determine where the water is coming from. More information is needed after that to determine the proper repair.



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Date/Time9/28/2015 at 9:23:08 PM

Hi Sam,

Al is right. You have to find the source and then the repair will be obvious. Could be simple caulking or epoxy injection. Could also be condensation if moist air is getting under the insulation blanket.

Good catch spotting it and asking the question!

Good luck with it.

Jim Kuzma

Kettleby Handyman

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Date/Time9/30/2015 at 9:02:31 PM

Hi Sam,

Is your home new, as in less than 2 years old or older? My assumption would be an older home due to the fact it does not have top to bottom insulation as newer homes require it. But if it is a newer home, it could be as easy as putting a de-humidifier in the basement as that could just be the water and coondensation from the concrete itself pooling. If not, then it is more than likely you have a crack line as almost all new build homes that install the windows at the time of the concrete pour, will almost 95% of the time have a stress crack starting from the bottom corner of one side of the window. The only real way to determine the cause and severity is to remove the insulation wrap in the affected area and observe.

The real problem lies in the fact that if water is already getting through the outside in, a fix for the inside is really only temporary and may be looking into waterproofing the foundation outside.

It could be just as simple as a small hole on the corner or under side of the window allowing water to come inside, if that is the case you can simply get some exterior caulking and re-caulk around the window and that should do the trick.

Really the only way of knowing is to open it up and proceed, and then you will be able to determine the cause and possible solutions. It depends how water tight you want your home and how much you want to spend, you may find someone willing to just epoxy fill the crack and be good with that.

Good luck with it though.


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