Frost on concrete foundation interior wall

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Posted by: from Thunder Bay
1/7/2021 at 5:26:03 PM

Hi there,

I just bought this house last summer.

Since the weather has gotten colder (Canada) I noticed the concrete walls in the basement (unfinished) are wet and have a thin layer of frost on them. We've just recently had a few warm days and I have noticed a small puddle of water forming from the frost melting.

The walls currently only have insulation on them (as seen in the pictures below), no vapour barrier. Could this simply be a moisture problem? And would putting new insulation and vapour barrier solve this solution? Or is this a bigger problem?

Thank you in advance!!

Frost on concrete foundation interior wall
Frost on concrete foundation interior wall
Frost on concrete foundation interior wall
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Jeff from JTL Construction in Winnipeg
Date/Time1/8/2021 at 2:22:09 AM

Hello from Winnipeg. Dont sweat it its common we see it all the time. When insulation is pushed against frozen concrete wall it will also freeze to it and the frost when it gets warm melts. Please read article. Yes vapor barrier will help stop inside humid air from getting behind wall but in wpg its the cold air getting in pourius concrete wall.

Frost on concrete foundation interior wall
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Date/Time1/8/2021 at 9:35:09 AM


vapor barrier and insulations only work together hand in hand..

make sure you have a snug insulation in all spaces and a vour vapour barrier is continuous, sealed and is only on the warm side in side of insulation or it will sweet and condensate water

also need r 12-20 insulation to help problem also mositure can be from too high inside humidity and or (less likely) coming in from outside

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Shaukat from Sam & Fils in Montreal
Date/Time1/8/2021 at 10:09:18 AM

Hi, you should pay the attention outside the foundation wall.

You need a waterprooding outside the foundation wall and inspection of your french drain, to sold the problem completely. Hopefully I answered your question.

Thank you



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