
You would need to make sure it is acceptable to your metal roofing producer. However, I would not use styrofoam as it is too spongy. I'd suggest poly iso board.
Agreed to Todd's recommendation. Make sure whatever foam you use has the right compression strength for roof application.
We are putting a new metal roof over our existing shingled roof and our new addition. The new part is 1 and 1/4" lower than the existing shingled roof. Can we put 1" styrofoam and 1/4" plywood over before the metal roof goes on, or is something else better?
Thank you for the help. I'll look into a poly iso board.
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