Sealing top of exterior wall in vented attic
I am working on air sealing the attic of our 1940s home. It’s brick exterior with only 1×2 strapping holding the interior walls to the exterior brick with practically no insulation. Our second floor gets much colder in the winter. At the roof line, I found the gap between the exterior and interior walls is completely open. See attached drawing. Is it OK/recommended to seal those gaps? I was planning to seal the gaps by stuffing some insulation in and then spray foaming over the top to fill the gap. It’s very difficult to reach that part of the roof. Once I have the major penetrations sealed, I plan to spray the entire attic floor with spray foam before moving insultation back into place. I’m doing 1/4 of the attic at a time. I wasn’t sure if air sealing the exterior wall gaps would create moisture problems in the walls?
This is in Chicago, climate zone 5.
The attic is vented but doesn’t have a vented soffit. When we had our roof reshingled a few years ago they installed intake venting along the roof a couple feet up which then vents out closer to the ridge. When I was removing the insulation from the first section of the attic, it was pushed all the way to the edge, against the roof sheathing at the corners. Some of it was wet, unsure yet if it’s a leak (it’s been raining) or moisture buildup from being directly against the roof.
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