How would you insulate these gambrel trusses?
I purchased plans off of a site called barnplans.com for my detached garage project. I essentially was buying the stamped engineered plans for the site built gambrel trusses as the rest of the wall framing is pretty standard light framing.
This is for a 1 story garage with attic loft.
Shooting for a vented cathedral roof assembly, how would you insulate these scissor trusses? Or are my options simply to go for a hot roof with closed cell at the roof decking and opencell or can I do that same with plywood baffles below the roof deck with closed cell below the baffles and then open cell?
I was hoping to avoid foam all together and use a vented assembly and mineral wool batts. However I don’t know how the gaps between the cord members gets addressed?
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sayn3ver,
I would either install continuous baffles from eaves to peak, or use a top side membrane as Josh Salinger suggests in this link https://www.greenbuildingadvisor.com/article/building-a-vaulted-high-performance-and-foam-free-roof-assembly. Then fill the bays with cellulose.
The lower slope is steep enough that there will be some settling of the cellulose, so it probably needs to be dense-packed, although you might get away with loose-fill and allowing it to settle at the peak, where if the depth becomes reduced it was thick enough at the start that it doesn't matter.