site built baffle and rigid foam question
I’m considering a job to improve insulation in Zone 5 by having insulation below sloped roof (rather than on kneewalls and 1st-floor-ceiling/second-floor-attic). The roof is vented, so I’d use a site-built-baffle. When insulating the sloped roof (for visual see picture https://www.finehomebuilding.com/app/uploads/cms/uploadedimages/fine_homebuilding/articles/230/021230089_xlg.jpg), I imagine the insulation between the site-built-baffle (by roof deck) and rigid foam (below insulation material) would be thicker than the 2×6 walls. The foam layers would be around say R-38 batts (12”). I have attached a picture of my situation, where the red lines are my envisioned rigid foam above top plate and below batt insulation for thermal break. The entire cavity could be filled with say batt insulation, but would you use rigid foam and seal the blue piece in my picture? Thanks, and please let me know if I can clarify?
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