Hi,

I’m renovating a home in climate zone 6B.  I have a lot of 3″ fiberglass batts which we pulled from the ceiling.  The exterior walls are 2×4 with 2″ mineral wool.  Is it okay to compress the 3″ fiberglass and 2″ mineral wool in the 2×4 stud cavity?  

I’d like to attach 1-2″ of polyiso or eps with taped seams to the inside of the exterior wall.  Then frame a 2×3 or 2×4 wall with batt insulation as the interior walls.  

Thanks,