SIP roof panel over Remote style roof
In designing a roof for an off grid cabin I found an article on the JLC site about a design for a Passive house in Wildfire country.
The builders basically built a “remote” style building enclosure with no overhangs, wrapped the enclosure with the WRB layer and then added a 6″ SIP panel on top. The rafter bays inside the enclosure are rather shallow (2 x 6 treated rafters with “net and blow” cellulose in between them) but this building is built in California.
I was wondering how this approach might work in climate zone 6B? If the rafters were increased to 2 x 10’s or 12’s and then the entire building was sealed with a WRB then the SIP panel could form the overhangs.
Would this method also prevent a lot of the problems associated with using SIP roof panels ie. air and moisture getting through the seams and either entering or leaving the building enclosure? After all, the building’s roof sheathing on top of the rafters is completely air and water tight and then you could also seal the SIP panel seams as well.
If this method of roofing is feasible should you also add a cold roof (2 x 4 spacers with plywood sheathing on top) on top of the SIP panel in order to install metal roofing?
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