Venting a cold attic with a cupola
Hi folks,
I’m designing a 26′ long by 24′ wide addition for our house in Southeast Alaska. The addition will have a cold attic over a one-story conditioned space, with a 7/12 roof.
I’m thinking about how to vent the attic. Because the addition is an ell, I can only put a gable vent on one end if I go that route. I could also do a continuous ridge vent and soffit vents.
But for aesthetic reasons I’m curious about building a cupola. What is the modern approach to this? Should I aim for a certain vent area of the cupola, in consideration of the vent area of soffit vents?
Is there a good reason not to use a cupola, as long as it is flashed properly where it meets the roof?
Thanks,
JS
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Replies
JS,
Cupolas work great. The total area of the vents comes from your code. The proportion of vents at the soffits to that at the top of the roof should be 60/40 to slightly pressurize the attic which will help reduce air leakage from the building below.