Best way to insulate a roof without attic access…
On my new house design, it is a prairie style house with wide over hangs and low (3:12) pitches. I have a clearstory area that bumps up with a 4 way hip roof capping it off. Being the low pitch, and getting 14-16″ of insulation up there, it fills up a lot of the roof.
So my question is, what is the best method of insulating a roof like this where you have no access from above (blowing in insulation) and would prefer to not use spray foams (green and cost factor)? Obviously I could staple thick batts up there which isnt as ideal either. I have considered going with thick batts and then adding 2″ of rigid to the bottom of the trusses, installing furring strips, and then installing gyp to those. However with this I run into additional issues such as lighting boxes and things. But I think I could attach them to the furring strips, maybe, and was planning on boxing and sealing them out from above anyway. But after the cost and time to do all of this, its probably best to just shoot the thing with a few inches closed cell foam to seal it up, then install thick batts.
Any other thoughts?
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