Low-Slope Roof: Where to Put Insulation
I have a large connecting hallway in a new addition I’m building that has a vented roof here in Zone 4 (1 hour north of Raleigh). The small challenge I have is that the micro-attic area over the flat ceiling is so small that I wont have access to this area after we complete construction… So it got me thinking, is there a better placement of insulation in this scenario.
Here are a few of my questions:
1 – if I move the insulation to the rafters, will the small open space above the sheetrock be “stale” and possibly “smelly” over time since there’s no direct conditioning of this small air space.
2 – Would insulating the flat ceiling (perhaps with dense pack cellulose) give me better “buffer” against the unconditioned air in the micro-attic and avoid any “smells” from migrating to the space below?
3 – Are there practical or performance advantages that either location provides?
4 – Would baffling the rafters and filling the entire space with something like 1/2 foam, or even dense packing the entire space be the more “fail safe” way to treat this space?
Thanks in advance for your suggestions / comments!
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