Return to the Flooring Forum | Post a Follow-Up

insulating floor over unfinished basement (vapor barrier?)

Posted by budman328 (My Page) on
Mon, Jan 28, 08 at 14:52

Not sure if this should be in the floor forum or an Insulation forum but here goes anyway. I have a tile floor in the kitchen over an unfinished section of basement. The basement drops to 55 degrees in the winter obviously making my kitchen tile floor cold. I have very easy access to put some R13 fiberglass up into the joists below the kitchen footprint. My question is about CONDENSATION. I'd rather have the paper side facing the basement (which is a bitter nice to look at than fiberglass). With the 55 degrees basement and 70 degree kitchen floor do i have to worry about condensation being created at all? i'm over-worrying about that right?

Paper side of insulation should usually be on the warm side, if i push it up into the joists i'm having the paper on the cold side. I don't want to be creating a moisture issue by doing this. but its only a 15 degree differnce at most.. does moisture form at 15 degree difference?

Follow-Up Postings:

RE: insulating floor over unfinished basement (vapor barrier?)

The kraft paper needs to up tight against the subfloor... no air gaps there. Instead of stapling you can use the wire insulation holders that snap in between the joist.

You can get condensation.

RE: insulating floor over unfinished basement (vapor barrier?)

okay so i understand i have to get it up in there tight, but are you saying i definitely need to have the paper side touching the floor (touching the warm side) so from the basement i'd be looking at the fiberglass and not the paper?

RE: insulating floor over unfinished basement (vapor barrier?)

Save a few $$ and buy unfaced insulation & use the wire clips to hold it up or nail some furring strips perpendicular to the joists.

RE: insulating floor over unfinished basement (vapor barrier?)

If you buy faced insulation the kraft backing should go firmly against the conditioned side. On the other hand you could use the unfaced type there like the previous poster said. Either way you will still see the insulation from below.

If you don't do this it may, or may not, come back to bite you one day.

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Flooring Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Please review our Rules of Play before posting.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here