I have a 1940 1.5 story home where the previous owner finished a living space in the attic. ( 1 bedroom with attached bathroom w/2 sinks, toilet and tiled in shower) It gets cold up here in Zone 6 (North Dakota)
After about 1 year, we realized the Insulation and ventilation was not sufficient, there was no vapor barrier or drywall, we had condensation issues, and spray foam was suggested as the best option. I had local company spray the foam. I went with their suggestion of flash and batt with 3" minimum 2lb closed cell foam sprayed directly to the roof deck, and plan to finish it myself by adding r13 un-faced batts and drywall.
I am unsure on how best to handle the knee wall areas. I've read that: flash and batt is tricky as if you have too much fiberglass, the dewpoint can move from inside the sprayfoam, to the face, and cause condensation on the face of the sprayfoam.
1. My thought on the 'best' solution would be to remove the knee wall and drywall all the way to the corner. (looks like previous owner added it, but from what I gather it would require a structural engineer to tell me it's not structural before I can touch it, and would cost $300-400 for them to come out and tell me yes/no)
2. Or should I fill that tiny knee wall area with fiber, and dry wall it. I'll likely already have leftover insulation to fill this area. My concern is that heat from the main floor of the house could fill this area, and potentially cause condensation on the face of the sprayfoam.
3. Similar question, do I just fill this area above the lights with fiber?
MS Paint (
) and Pictures are below, thank you for any advice!
EDIT: I didn't realize I [img] [/img] don't imbed into this forum. For now, links are below.
http://i793.photobucket.com/albums/yy212/Slopel104/atticmspaint_zps71f30640.jpg
http://i793.photobucket.com/albums/yy212/Slopel104/attictop_zps55841170.jpg
http://i793.photobucket.com/albums/yy212/Slopel104/atticsprayfoam_zpsea442617.jpg
http://i793.photobucket.com/albums/yy212/Slopel104/atticskneewall_zpsf265ab9b.jpg
http://i793.photobucket.com/albums/yy212/Slopel104/atticsshortkneewall_zps73daf226.jpg
http://i793.photobucket.com/albums/yy212/Slopel104/atticnkneewall_zps472c35b4.jpg