Rigid foam over sheathing in Florida
Rybuffett
| Posted in General Questions on
I’m in SWFL and need a new roof. I wanted to take the opportunity to improve my energy efficiency, but I’m having a hard time finding any roofers with any experience in energy efficient roofs. For durability and efficiency, I wanted to go with a metal roof.
Can rigid foam be placed over sheathing in Florida and meet code?
Anyone know a good resource to find energy efficient roofers?
Any other things I should consider before replacing my roof?
Thanks!
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Replies
In SWFL, 2021 IECC R806.5 has all the requirements to insulate a conditioned attic. I always spec a peel and stick WRB to seal the roof decking, then you can install 1" R5 min. required in CZ1 & CZ2. I recommend to install 1.5" R10 polyiso to match a typical 2x4 nailer at the roof edge perimeter. Then install 1x4 and the metal roof on top.
You also need to install 6" R21 min. ocSPF under the roof decking to have a full R30 min. insulation in your attic.
I recommend you watch these video: https://www.youtube.com/watch?v=DpxLi_Rm30s, https://www.youtube.com/watch?v=8XSyXCTTfpQ
Thanks for the info! I like Matt’s videos, learned a lot of great info there.
Any tips on finding a contractor in SWFL that is willing to replace a roof this way?
Thanks!
Maybe you need a more general contractor. Some one who does more than roofs. Someone who will do the insulation and hire in the roofer.