Devil’s triangle and cathedral ceiling insulation
I’ve been reading this forum for a long time now and am at the point where I’m beginning the work.
I have a 1.5 Story Cape. Roof is vented, I am unable to build an unvented roof at this time.
I have derived a plan to insulate the kneewalls and sloped ceiling but am concerned that my plan may lead to a moisture build up. Any advice would be greatly appreciated.
Sloped Ceiling (Roof Sheathing Down):
1) Continuous and Sealed Ventilation Chutes from the Unconditioned Triangle to the Attic Space
2) Fiberglass Batt Insulation
3) Continuous Layer of XPS Board Across rafters Taped at Joints)
4) Finished Wall Board
Do I need a spacer between layer 3 (XPS) and layer 4 (finished sheetrock)?
Kneewalls (Outside to Inside)
1) XPS Board Adhered to back of 2×4 Studs
2) Fiberglass Batts in Studs
3) Finished Sheetrock
Will the XPS board being adhered to the rear of the studs trap moisture in between the sheetrock and XPS leading to the mold/rot inside the wall cavity or is this an acceptable way to boost the insulating value and airtightness?
Sorry for the length, please let me know if any more information is needed to advise.
I appreciate any help.
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