Replies

1. 
   Guest_ | Jan 01, 1999 02:22am | #1

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   David,
   You describe a classic situation for condensation on a poured concrete wall. What is happening is that the wall is cold and moisture from the basement is passing through your 2x4 wall and condensing on it. The correct way to insulate and finish a wall like this is to apply styrofoam (not beadboard) directly to the wall and seal the joints and edges with caulk and tape. I don't think you need to seal the inside of the wall unless you think there's moisture actually coming through it. (Another problem altogether) We normally use 1 1/2" styrofoam and it provides plenty of insulating value without using any more in the wall itself. If some sloppy basement contractor left big bumps and ridges on the walls , you will have to knock them off before sheeting with the foam.....

2. 
   David_K._Reed | Jan 02, 1999 07:57am | #2

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   Thanks for your reply. From what I've read about condensation, I suspected that the condensation was caused by the lack of the vapor barrier and the incorrect insulation product and installation. I really appreciate your caution to use styrofoam versus beadboard. I had been tempted to re-use the beadboard, but I will refrain from that for now. Thanks again!

1. 
   savoy_ | Jan 03, 1999 08:00am | #3

   *Dave, I have also used the 1 1/2 inch styrofoam but would caution you to also include a vapor barrier of vinyl over it as styrofoam is not totally vapor impervious. Ensure that the moisture is really from condensate and not exterior moisture infiltrating through the wall. The slope of the ground outside the foundation often subsides with time and can easily be built up to allow proper drainage. Good luck Savoy-29

3. 
   David_Reed | Jan 03, 1999 08:00am | #4

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   I am reinsulating a formerly finished poured concrete basement, and
   I'm in a quandry as to what to do. The basement has had condensation on the concrete, and in one small spot, mold and mildew on the drywall. For various reasons, I do not want to remove the existing stud
   framing for the walls. *The walls had been insulated with rigid insulation (styrofoam and beadboard)
   precisely cut to fit and placed a couple inches away from the concrete walls
   (without a vapor/air barrier). I am considering painting the concrete on the interior side with a
   sealant material, affixing the existing insulation directly to the wall,
   installing a vapor barrier to the interior studs and ceiling, and then
   installing greenboard drywall. Is this a sound approach? What other
   suggestions/advice can you provide for this scenario? (PS-- our log home
   rests on this basement foundation).