Owens-Corning mineral wool compared to Roxul Comfortboard?
I’ve noticed that our local building supply store carries Owens-Corning R-16.8 “Safing Fire-Stopping Mineral Wool Insulation”. At a 4″ thickness, that’s something like R-4.2/inch.
In comparison, Roxul Comfortboard 80 R-6 48-sq ft Unfaced Rock Wool Batt Insulation with Sound Barrier (24-in W x 48-in L) (This is their 1.5″ thick Comfortboard) is R-4 per inch.
My guess is that the Owens-Corning product is less rigid and handles more like a fiberglass bat. Paradoxically, I’d think a “bat” is less rigid than a “board” but not having seen the Owens-Corning product, I am not sure. It may not be a good candidate for exterior “rigid” foam sheet style installation if it is indeed more like a fiberglass bat.
Has anyone used the Owens-Corning product as exterior insulation? How does it compare?
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