How to vent an insulated shop attic
Adam Emter - Zone 7a
| Posted in Energy Efficiency and Durability on
I’m building a 40×96 shop. Post frame, with interior OSB, taped as an air barrier. The roof will be metal, with cellulose blown in on top of the ceiling OSB. All utilities and lighting will be using conduit, so there will be virtually no penetrations into the ceiling, except for a whole-house fan which will be insulated and sealed from the underside in winter.
There won’t be soffit overhangs, so I’m not planning for a vented ridge either. Would gable vents take care of attic venting? Thinking about using two 18×24″ vents on each of the north and south gables.
I’d appreciate any advice. Thanks!
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Replies
I should add, the roof metal will be installed on top of synthetic underlayment and 3/4" OSB.
Adam,
If you create a tight ceiling air barrier, confirmed (if possible) by a blower-door test, there shouldn't be any worries about moisture accumulation in your attic. Gable vents should be adequate (as long, of course, as your local code authority agrees with this approach).
For more information, see All About Attic Venting.