Northern Michigan un vented, un air conditioned Cabin roof design.
After reading several articles, opinions and Blogs I have a better understanding of the moisture vapors that exist and the problems they can create in walls and especially the roof. But I’m a little unsure of the proper design and construction for my great lakes, shore line cabin roof design. I have detailed my current plan below. Could please you give input as to where my design plan is OK or deficient in proper vapor management for this environment and situation.
I’m building a Building a 12×28 cabin with a 1 ½ story loft on one end, in upper peninsula of Michigan on lake Huron shoreline.
It is typically a humid environment as the cabin is taking the west wind blowing off lake Huron.
The cabin will see intermittent vacation use mostly in the spring, summer, fall and some limited winter use. Heat (if needed) will be turned on and off at each vacation use. Electric heat, No air conditioning.

Starting on the exterior of roof, I plan to use hidden fastener steel Roof. A layer of standard felt paper under steel. Plan is to use 1/2” OSB or plywood for roof decking. Steel, Felt paper, OSB or plywood, will rest on 2”x10” trusses. Between the 2”x10” trusses I will have 10” of craft faced toward interior fiberglass insulation. Next 1” Dow foam board under trusses as a air barrier, followed by T&G wood for interior of ceiling.
Thank you for your advice,
Mike