Zone 4A residential insulation questions
I been working with a building supply company’s designer [gray haired guy, ex-contractor] who does design and cost build-outs. I’ve also had conversations with 3 reputable, referred, builders in the area.
My exterior dimensions are 40 x 44, no valleys or bump-outs. A walk out basement on the south gable and a loft on the north.
The south ½ of the roof will be 11 7/8 engineered I-beam cathedral ceiling. The north ½ of the roof [creating the loft] roof trusses designed to allow a ‘bonus space’.
After talking to these guys I’ve got an idea of what I can get and cannot get built in this area.
All 4 said they’d vent the cathedral and insulate inside 10” or so. He also has an insulator sub who blows anything I wish, including close celled. They will also vent the trusted section of the roof.
Question: How much of a space is needed for a vent in the cathedral ceiling to allow adequate airflow but maximize space for insulation?
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