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Community and Q&A

Junction Box for Lighting / Ceiling Fan Fixtures

jdchess | Posted in General Questions on

Choosing lighting for new construction in southeastern NC (CZ3). Ceiling drywall is the air barrier, so obviously, I want to avoid as many holes as possible and I want to use surface mount fixtures that I can air seal effectively. I plan to avoid recessed cans entirely.

Is there a particular type of junction box I should be looking at for all the light and ceiling fan fixtures that is considered air tight? Am I good air sealing wise as long as I stick to surface mount fixtures that use standard junction boxes? Those can be sealed effectively from the attic side it seems.

Does anyone have experience with the LED disc or wafer lights that look like a recessed can but mount in a standard junction box? I assume these can be air sealed more effectively than recessed cans? Something similar to this…!c9534090949!a98385144478!dc!ng&gclid=EAIaIQobChMIrO6AlaWt6wIVhYnICh1UUgBWEAQYAiABEgKbdvD_BwE&gclsrc=aw.ds

Thank you to everyone for the help and adivce.

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  1. Expert Member
    Akos | | #1

    Search for vapor-tight fixture/ceiling box at your box store. These have a lip with a gasket that buts up tight against the drywall. Might not be stock in warmer climates and have to order it online.

  2. jdchess | | #2


    Thanks for the info. Are there any particular type of surface mount fixtures that are more conducive to air sealing than others, or all pretty much the same assuming standard junction boxes?

    1. Expert Member
      Akos | | #4

      I've used some of the Halo low profile LED lights. These have a gasket on the back. They seal OK if you are careful with tucking the wires, but I would still rather have an air tight box behind it.

  3. Expert Member
    NICK KEENAN | | #3

    For a ceiling fan you have the additional consideration that the box has to handle the weight and vibration of the fan. It needs to be rated for that purpose.

    Here's something that looks like it might work:

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