Unfinished walk-up attic: best way to get ducts into conditioned space?
Climate zone 4 (central NC). I want to bring the HVAC ducts in my unfinished walk-up attic into conditioned space, which I think basically means I want to insulate the walls and roof deck of my attic. Goal is to preserve ability to finish the attic somewhere down the road, but that might not happen for years (or ever), and I’d rather bring my ducts into conditioned space as soon as I can.
I had previously been planning on spray foam, but I’ve become increasingly uncomfortable with the (small) possibility of being one of the unlucky few who has odor/toxicity issues.
Based on attached pictures (I know, the ductwork is terrible), is spray foam basically my only reasonable option?
Rafters are 2×8, so I thought about having the depth expanded and using baffles & fiberglass (or rock wool). A challenge with that, however, is that as shown for example in picture 2, there are certain portions of my roof deck that do not extend to a soffit vent due to roof features like dormers. My understanding is that every rafter bay needs to be vented. So does that basically kill (or greatly impede) the furring + baffles + fiberglass option?
Would building a knee-wall around the ducts and covering them with blown-in cellulose or fiberglass do any good?
Are there any other non-spray foam options that a typical contractor would have the skills to do? If anybody has insulation contractor (spray foam or otherwise) recommendations in the Raleigh/Durham area please let me know.
Thanks for any input.
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