I need to address the insulation situation specifically above the 2nd floor bathroom. (Pic is not the greatest) The bathroom is located in the octagon portion in the attached picture. I can access this area via the walk up attic, bit it’s tight quarters, fun times.
The joists are 2×10’s which run “into” this octagon area. I would presume I should cut square’s out of some left over XPS and foam them in place similar to what I did at my last house which was a cape cod. At my previous house I did this behind kneewalls, though unclear if this is a waste of time as the walk up attic is not finished. Hopefully that makes sense
Because I am dealing with 2×10’s I would assume R 30 unfaced FG? Would I then lay another layer of R 30 perpendicular to the joists? Because the roof tappers down and I have minimal depth towards the exterior wall , the 2nd layer of insulation may be in contact with underside of the roof deck. Will this be a problem?
Does insulation perpendicular to the joists need to be faced FG or does it not matter? I will do airsealing around the electrical penetrations and have already foamed around the Panasonic fan before doing the insulation.
While blowin would be an option were talking about 25-30 sqft and I just cant see going through the hassle of trying to rent a hopper etc.
I am in Zone 6 B
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