Can isocyanurate paper/fiberglass faced insulation board be used on the inside of a wood stud framed wall?
Have old house with 4″ cavity in wood framed walls. Exterior has 1″ sheathing board with 6″ wood shiplap siding over it. Can we put isocyanurate bd on interior of walls to increase the R-factor before we sheetrock top 4′ and wood veneer the bottom 5′ of the wall. Is their any increased fire hazard or other concerns
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Replies
Bill,
Yes, you can install polyiso on the interior side of your walls. As long at the rigid foam is covered by a layer of 1/2-inch drywall, there is no fire hazard. For more information, see Walls With Interior Rigid Foam.