GBA blog dated 2015: “How to Insulate a Foundation”
I’ve read many articles from various reputable sources as well as this one from GBA http://bit.ly/2lAt69b and I have a follow up question…
Martin, you’ve recently replied to my retrofitting basement questions regarding insulating a 1974 bungalow in climate zone 7a, so thank you.
Based on all of the research I’ve done over the past few months, I’ve been wondering something for a while… what’s the feasibility of insulating an internal basement foundation with a continuous thermal bridge in 2 different layers… the upper half portion, say 4 feet, with a higher density and greater air & vapor impermeable product such as XPS or polyiso, and insulating the bottom half (4′) portion with a slightly lower R-value and more air & vapor permeable product like EPS or Roxul ComfortBoard?
Then the usual 2×4 or 2×6 stud wall with batt insulation and appropriate vapor retarder?
Just curious if there have been studies on this and what the effects or advice is?
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