Proper upper roof sheathing support for Comfortboard 80 exterior insulated roof

I am building a timber frame roof system with a 4.5/12 pitch. Roof decking is 2×6 T&G. My current plan is to use 6″ of Rockwool Comfortboard 80 above roof… I am building a timber frame roof system with a 4.5/12 pitch. Roof decking is 2×6 T&G. My current plan is to use 6″ of Rockwool Comfortboard 80 above roof…Read MoreGreenBuildingAdvisor