Can I use polyiso foam for interior basement wall insulation?
A recent GBA article (http://www.greenbuildingadvisor.com/community/forum/gba-pro-help/18454/w...) discussed options for internal foam insulation on a wall already with external insulation. Another article (http://www.greenbuildingadvisor.com/green-basics/rigid-foam-insulation) tells us that polyiso shouldn't be used for below-grade applications because it can absorb water. Our design includes a poured basement wall with 4" of internal XPS foam. I am concerned about external foam being mangled during backfill. I'd prefer to use polyiso over XPS because of the higher r-value per inch, but I'm not sure if it will work well for interior basement walls.
Posted Nov 2, 2010 11:20 PM ET
Edited Jun 20, 2012 12:33 PM ET
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