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hvac return

GBA Editor | Posted in Energy Efficiency and Durability on

i inspected a building with two returns in a 463sf hallway ceiling and supply registers in every office space of a 3399sf cinder block building with doors shut most of the time. it’s hot in the summer and cold in the winter. should i install transfer grilles in the doors or cut the doors? do transfer grilles work just as well when installed in a door?

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  1. Riversong | | #1

    Either undercut the doors for 1" clearance or install transfer grills.

  2. homedesign | | #2

    Not sure how big those offices are....
    Dedicated returns are an option...jump ducts...high and low thru the wall transfer grilles.
    Return air should be related to the size of the supply.
    Think about acoustic privacy too.

    Even In residential 1 inch undercut doors does not cut it.
    You need to work with a mechanical contractor.
    Pressure balancing is important and it has more ramifications than just comfort.

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