Damp between insulation and exterior wall
I’ve been trying to upgrade the insulation in our 1950’s family home in Southern-Ontario and have been following some of the advice I found on this site. I have air sealed as many leaks as I could around ceiling fixtures, interior wall top plates, and the gap between the ceiling drywall the top plate of the exterior wall. I used acoustic sealant and expanding foam where applicable. I have also added some new fiberglass batts and made sure to fit them over the top plate, around studs, etc.
Today I noticed some dampness and even some frost between the exterior wall boards and the new insulation. As you can see in the attached pictures there is still a big gap between the exterior wall and the top plate, as well as the attic studs.
Do I need to go back and seal this gap as well? I don’t think I saw any recommendations on this site or others about sealing this area. Is it enough to do the top plate gap, or do I need to go up the rafters as well?
Thanks very much for any advice.
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