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Insulating a Vented Roof With Blown-In Cellulose

7echo | Posted in General Questions on

Zone 2A, hot and humid.
I was planning to air seal the ceiling from the attic and blow in cellulose. The house has soffit vents. After looking closely I realized there was no ridge vent.
It is difficult to get high R value all the way to the exterior walls with the 4 in 12 pitch, need a baffle, and the space is tight.
Its a simple rectangular hip roof, 1950s, 1100 square feet house.
What are the best options here? I am wondering if I seal the soffit vents can I blow the cellulose packed against ceiling drywall up to roof deck? Then doing the vapor diffusion at ridge. But that may be beyond budget.
If I keep it as simple as possible and install baffles and blow in the cellulose do  I need a ridge vent?

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  1. Jon_R | | #1

    Size for 1/150 of the area of the vented space and code allows you to use any mix of soffit and roof vents.

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