Insulating an Attic With 2×6 Rafters
I live in NJ in an old 1930’s house. I’ve only got 2×6 rafters in the roof (which is interesting). My attic is currently uninsulated and there’s a lot of HVAC equipment and ducts up there. (Yes, I’m a poster child for disaster).
I’ve been looking a how to best insulate the roof. So far I seem the settling on add 6″ of closed spray foam to the rafters and create an unvented assembly . The rafters are 2″ x 6″ (actual not nominal) so I feel like close-cell spray is the only option.
I’ve read a lot of articles on the site (https://www.greenbuildingadvisor.com/article/a-new-look-at-conditioned-attics) and agree in general with the sentiment – don’t condition an attic however I have little to no choice.
So my question is – it’s 6″ of foam going to cause a problem as it will create an unvented roof assembly?
Exterior foam on the roof 4-6″ was an option but no one seems to want to entertain a job.As an aside, I read something on this site the other day where a contractor was explaining that the way he’s set up the company 1 week jobs are his target and he’s figured out ho to make money that way so that kind of makes sense in this area where I live — the volume of jobs means they need to be highly predictable.
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