Remove builder installed fiberglass nailed to basement walls
Location- Denver CO Climate zone 5
Hello my name is Graham,
I am looking to insulate/ finish a basement in a newly built home. The walls currently have R-10? or less? fiberglass roll insulation with plastic barrier nailed directly to the foundation walls. Seems like the standard for insulating basement walls in new homes (that I have seen in Denver)
I am thinking that I should remove the fiberglass, air seal the rim joist, add appropriate thickness EPS to prevent condensation. Then I could reattach the existing fiberglass to get me to R-20 on the basement walls (or purchase new).
Interested to see if anyone else has dealt with removing builder installed fiberglass on basement walls to achieve a better result. I think I know the answer to this question- it just stings a little to remove the brand new fiberglass.
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Replies
YES, i would jerk it off and go with xps or eps IF ANY CHANCE of moisture. If no chance of moisture then polyisocyanurate is a better option. THIS FOAM BOARD MUST BE COVERED with 1/2" drywall or an equal barrier due to fire concerns.
Normally, rigid foam/2×4 framed wall/ drywall.
Only thing I would be concerned about is the "plastic barrier" trapping moisture because the cement will wick. Use latex paint on the drywall to prevent trapping moisture after poly is removed.