I am remodeling a bathroom with a 2/12, 2×6 @ 24″o.c. stick roof. I bought new skylights with inclined flashing for the low slope. How should I ventilate the roof? Eave and Ridge, or eave and low profile roof vent? Is it bad to have a ridge vent or low profile vent on a low slope (2/12) roof? I also need to penetrate the roof for a bath exhaust fan. Any special kind of vent stack cap needed? Also should I use 3-tab or rolled roofing. I plan to use a waterproof membrane under the shingles or roll on the whole area.
Now, what about insulation? 6″ batt insulation won’t give me much r-value and won’t leave any venting space. Can I use rigid foam with a space between roof deck and insulation and caulk the contact between the foam and rafters for a vapor barrier?
Replies
Don't vent. Use spray foam right under the deck.
Andy Engel
Senior editor, Fine Woodworking magazine
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