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Community and Q&A

Exhaust Fan duct design

artisanfarms | Posted in Energy Efficiency and Durability on

In the house I’m renovating with an eye towards ‘Pretty Good’ efficiency, the kitchen, guest bath and laundry rooms are contiguous.

I’d like to vent my kitchen exhaust, dryer exhaust and exhaust from the guest bath thru the same roof penetration.  What is the best way to set up a manifold and, if needed, a secondary fan to accomplish this?

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  1. Patrick_OSullivan | | #1

    You really don't want to do this.

    (1) I'm not even sure if it's code permissible.
    (2) Each appliance would need to be back damped from each other, but you'd still run the risk of pushing air meant to be exhausted back into the house. You really don't want to risk kitchen effluent getting pushed into your bath fan or dryer, as an example.

    You mention roof penetrations. However, all of these items can be side wall vented, and often are.

  2. Expert Member
    NICK KEENAN | | #2

    You can't run vents together. You could do an ERV for the bath and get a ventless dryer. For the kitchen vent you want an electric damper that closes tight when it's not in use.

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