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How would you insulate these gambrel trusses?

sayn3ver | Posted in General Questions on

I purchased plans off of a site called 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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  1. sayn3ver | | #1


  2. Expert Member


    I would either install continuous baffles from eaves to peak, or use a top side membrane as Josh Salinger suggests in this link 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.

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