Extra Attic Insulation. Can I add polystyrene panels over existing fibreglass batts?
I have access to 6in thick polystyrene panels which I would prefer to re-use rather than take to the garbage dump. Can I lay them over existing fibreglass batts to increase the insulation in the attic ? The house is 4 yrs old so is up to code and is located in Ontario, Canada where the winters are cold. I'm worried about causing a moisture problem.