Insulate vented cathedral attic ceiling above gable joint
Im deep in my attic insulation project. Here is my plan: I’m using 1-inch foam to create a 1 inch air vent against underside of roof. I’m sealing with spray foam. Then will come 3.5 inches of unfaced rock wool up to the bottom edge of rafters, and then 2-inch polyiso layer under rafters, followed by 5/8 drywall.
Ive got 80% of the ridged foam cut and cobbled in and have one more stretch to do, but it runs over the opening to a gable running perpendicular to the main roof. This section has access to the main ridge vent, but not the soffit venting. What’s the recommended approach here? Do I follow the same approach, but just seal off the bottom of the venting gap since it can’t go down to a soffit? So, is it ok to just have ridge venting for this section without soffit venting?
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