Energy efficient and durable roof design
I am planning to build a 1 1/2 story in zone 6A in deep snow country (ground snow load is 60 psf). The roof design is a simple gable with one doghouse dormer. I would prefer not to do a hot roof. Because of the snow, I’ll have to vent the roof sheathing regardless, so I’d prefer to go with what I believe is the most straightforward option. Thus, my original plan was to vent the roof and fur out the bottoms of the rafters to provide lots of room for insulation (R50-R60) and use a high-quality smart vapor/air barrier. My only concern is the inability to vent the roof from the eaves above the dormer (obviously the ridge vent is still at the ridge) . Should I install spray foam in this specific area instead? Is this relatively small area worth losing sleep over? How do people usually deal with this detail?
I attached a drawing below Green=Ventilation Red=What I perceive to be inadequate ventilation
Thanks in advance for your expertise and wisdom!
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