Best insulation for ventilated crawlspace
For a ventilated crawlspace in a small house near (relatively humid) Asheville, NC, which would be better, Roxul ComfortBatts between the floor joists, or Roxul ComfortBoard nailed to the bottom of the joists, or foil-faced polyiso nailed to the bottom of the joists? Any of these choices would likely be better than the fiberglass batts that are presently hanging at weird angles. I worry about creating an empty cavity if I attach the insulation to the bottom of the joists. I'm not sure I can afford to insulate between the joists and under them. I have read your article on Building an Unvented Crawl Space and decided that is too much work and I don't like the risk of higher radon levels. What are your thoughts about the three options above, and is there some other better option I have not considered?
Posted Aug 8, 2014 8:23 PM ET
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