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Multiple Apartment Exhausts

pipe4zen Member Posts: 108
What would be the the best way to run bathroom exhaust for apartments, 3 levels, two units on each floor, without having 6 penetrations through roof? Is there a manufacturer that anyone would recommend.

Also, the best way to add fresh air ventilation to each unit, centrally if possible.

And last if I'm not mistaken , codes won't allow for kitchen hoods to be tied together, each unit must have invidual hoods.



  • BillW
    BillW Member Posts: 198
    Bath exhausts

    Bath fans typically move about 70 cfm, and if you have 6 of them, the max would be 320 cfm.  This would probably happen in the early morning or early evening, when people are taking showers, to exhaust the steam.  During the day, operation will be sporadic.  If you are running the ducts thru un-conditioned space, use insulated duct, so you minimize condensation, and potential water issues.  Use a bird screen/ insect screen on the outdoor exhaust port to keep the critters out.  I don't see any reason why you couldn't tie each bath exhaust into a central trunk to exhaust out thru the roof or sidewall, but make sure that this is sized to handle the max flow, but refer to your local codes for their requirements.  If you can, leave access for cleaning because cosmetics, hair products ad other items used in the bath can mix with dust and eventually clog the critter screen or the vents themselves.
  • pipe4zen
    pipe4zen Member Posts: 108
    Bathroom exhaust fans

    Thanks for the reply.

    I'm looking into American Aldes multi port units, however they recommend on 20-25cfm per bath, continously with air flow regulators for balancing.

  • BillW
    BillW Member Posts: 198

    I used 70 CFM as a rule of thumb, since that's the "average" heater/exhaust fan/light combo capacity.  I haven't had any experience with the units you are planning to use, but they look like nice products on their website.
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