Durability of Unvented Roof with Fiberglass Batts
I just bought a 100+ year old home in climate zone 6A. The seller recently finished the attic space and provided me the attached drawing of how they insulated the attic ceiling. All insulation is fiberglass batts.
Despite the quality of their other renovations, I am certain they didn’t pay particular attention to air sealing or vapor management.
How high risk is this set up for mold, rot and failure?
I expect we will need to replace the roof in 3-5 years, at which time we can add continuous exterior insulation or address any issues from the top side.
As long as there is no bulk water intrusion, is that time horizon safe enough to not bother touching this?
Do I need to rip it open and address it ASAP?
GBA Detail Library
A collection of one thousand construction details organized by climate and house part