Latest Discussions : Basement & Foundation

Stever

05:37PM | 08/20/02
Member Since: 08/19/02
2 lifetime posts
I heard so many philosophies on this topic. I have built my walls out of 2x4s and stood the wall about 1-2 inches away from the poured concrete foundation wall. I'm ready to insulate. One school of thought is to stuff thicker kraft faced insulation (R19) to fill the entire cavity the other is to go with thinner kraft faced stuff (R13) and leave a gap between the poured concrete wall and the framing. I also heard the idea about putting a sheet of plastic on the wall first then do the insulation. What's the deal??

GlennG

01:27PM | 08/22/02
First, you do not want a double vapor barrier. It will only trap moisture between them.

You want to keep the vapor barrier facing the living space side of the wall. This will be the warm side of the wall in cold weather. Warm air (containing more moisture than cool air) should be kept from infiltrating the insulation where the moisture will condense into water when it meets the cool air. The best method is to forget the Kraft paper face and go with R-13 friction fit insulation (No paper face). Leave an air space against the concrete wall to keep any moisture from wicking into the insulation. Then cover the wall and insulation with 6-mil polyethylene plastic. This will create a much tighter continuous vapor barrier.

Glenn

octoruss

05:44AM | 11/01/02
Member Since: 10/31/02
6 lifetime posts
Glen, I'm very interested in this topic, but want to make sure I understand you correctly as I was a little confused by your reply.

I understand I should leave 1-2" between the new wall frame and the foundation wall, and that I should stuff R-13 insulation into the frame. But I'm not sure where to put the plastic sheeting for the vapor barrier. Does this barrier attach:
1) Directly to the foundation wall, or--
2) to the back of the wall frame, or--
3) to the front of the wall frame

I'm assuming the correct answer is #2, so that in order you would have drywall attached to the frame, insulation between the frame, then plastic sheeting holding in the insulation and facing the foundation wall, then lastly the foundation wall. Is this correct?



Post a reply as Anonymous

Photo must be in JPG, GIF or PNG format and less than 5MB.

Reply choose button

Anonymous

Post new button or Login button
Register