Ventilate kneewall attic space?
I finally took care of my second floor kneewalls which had 6 mil. poly on the back as well as open floor joists (2×10) and open ceiling joists (2×6) which communicated with the attic space above the second floor ceiling. All these spaces were insulated with fiberglass.
I used 3/4″ foil-faced polyiso on the kneewalls, and in joist and rafter cavities, all taped, caulked and foamed. I will also be plugging the rafter cavities from the upper attic.
My previously well-ventilated assembly has been plugged! Do I need to concern myself with ventilating the two, now separate, attic spaces? The lower one has full soffit venting. The upper one has two gable vents. I would eventually like to add more blown insulation to the flat ceiling areas.
Should I go with roof vents to exhaust the lower section and maybe ridge vents for the small upper section? I’m in CZ4, bordering on 5 in NJ. Thanks in advance. I learn so much from this site!
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