Installation & Venting over Foam

Guest User
4/17/2017
I'm building a small "tiny cabin" and in the process of ordering a roof. Leaning towards metal. The structure is in the mountains of North Carolina. We have tons of rain in the summer, so I want to make sure I do this right. The temperatures are extreme, summers it can be 90-100* and winters can be down to 0* for a week or so. We won't be living in this, but more of a weekend getaway. It's a small roof, only about 16' x 20' and 3 1/2:12 pitch. Cold roof. I've got ZipWall decking down. My hope was to use 2" XPS foam board over the decking and then a layer of underlayment over the foam. I would like to create some sort of airflow between the foam and metal roof. I have looked at the Corvent systems for both the eave and decking. Would there be another option to create airflow on the decking? I know I could use 1x4" lathe but I would have to run them horizontal, which would block the vertical air flow to the top of the roof. I don't think I'll need an underlayment under the foam, since the ZipWall system acts as one already. Would it hurt to have one on top? Should I use an Ice & Water Sheild? Any help would be greatly appreciated!
Eric Novotny
An informed customer is the Best Customer!
4/18/2017
Cross batten the roof if you don't want to run the corvent battens.

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