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Conditioned attic ventilation question

albertoarriaga33 | Posted in Energy Efficiency and Durability on

Hi All,

I have a question regarding conditioned attics. I’m building a home in a hot-humid climate where the mechanical systems will be placed in the attic. For this reason and also air sealing reasons, building a conditioned attic seems the right way to go. The question is not regarding the assembly but regarding the actual conditioning of the attic. As Joe Lstiburek says, it’s not wise to call them “unvented attics” but rather conditioned attics. For this build we cannot rely on leaky ductwork to condition the attic because close attention will be paid to seal it well. My proposed solution is to provide a register at the ridge that returns air to the ERV. Makeup air would be provided by passive vents connecting to the hallway. Regardless of whether this solution works, can anybody recommend ways to couple the attic space to the HVAC system? This is in the interest of keeping the air moving and preventing accumulation of moisture in the attic. 

Thanks in advance!!

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  1. Jon_R | | #1

    This is an attic that, due to fire reasons, cannot be treated the same as any other conditioned room?

    1. albertoarriaga33 | | #2

      Jon R,

      No fire concerns due to the interior bays and roofline having 5 inch rockwool batts.

      1. Jon_R | | #3

        Then you can condition it like any other room - with a register and a return.

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