Insulating PWF basement
The "new plan" is to insulate the outer wall of my PWF basement with strips of EPS between the studs since I've found the material at a cost lower than mineral wool bats.. I'll cut strips of the sheet goods and install them much like bats for a total of 7 1/2"thickness. Inside the foam will be 3 1/2" of mineral wool as an ignition barrier for a cavity r of 45. Since my outer insulation is not air permeable, I should not need an interior vapor/air barrier. The question is is a friction fit of the foam enough of an air seal to prevent condensation on the sheathing, or should I use can foam around each panel? .
Posted Jun 17, 2014 11:38 AM ET
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