Vented over roof on parallel chord truss
I’m about to commence a project and I’ve got all the details dialed in up to the roof and I’m leaning towards the following.
16″ parallel chord truss, 2/12 pitch, 16″ O.C with no overhangs. I would sheath it in 3/8″ cdx with all joints taped and then WRB on top, either felt or triflex. Then on top of each truss, I would put a parallel 2×4 either on edge or the flat, which would then fly out over the edge of the truss, creating my venting channel and soffit overhang. On top of the 2×4 purlin would then be probably 5/8″ zip system. I’m leaning towards just sheetrocking the interior side of the truss but worry about having it blown off by insulators. Otherwise I would probably go with 1″ polyiso and then strapping.
The logic being that I get a nice solid roof cavity to dense pack with cellulose and not have to go through the trouble of dealing with adding in baffles or what not to get the vented space.
Any thoughts and/or suggestions? I’ve attached my drawings as they stand…
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