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Community and Q&A

Installing new bathroom fan within old enclosure

longfieldl | Posted in Energy Efficiency and Durability on

We just remodelled the bathroom and in the process of moving stuff around a part of the old bathroom fan unit got lost and I cannot put it back together.
It breaks my heart to have to mess with the ceiling which has just been plastered and painted very neatly by a pro.
I realized that the enclosure is 11 1/2 X 10 1/2 inches and so a new fan with a heat lamp that I am looking at would fit entirely within this enclosure and the exhaust of the new one is aligned with the output in the old enclosure. Since a smaller opening is needed, I was thinking of using a very small frame made of hardboard that I would paint and try to make as discreet as possible, snug fit between the ceiling and the fan cover and painted like the ceiling.
So it would be en enclosure within an enclosure. Would this be acceptable and secure considering also that there is a heat lamp?
Thank you

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  1. Andrew_C | | #1

    If you look at a Whisper Green vent fan installation video (e.g.,, you'll see a)they do the installation from below, and b) there's a bracket that can fold up and then expand after you get it through the drywall hole. This may give you some ideas.
    And, if you get a bigger unit, you can just cut a bigger hole. It's always easier to make a small hole bigger than to make a big hole smaller.

    Hope that sparks an idea for you.

    P.S. I put in a couple of ventilation fans recently. I had to go into the attic to get the work done. I guess that if you've done it several times, you might avoid any trips to the attic, but some of it depends on the insulation situation.

    1. Expert Member
      MALCOLM TAYLOR | | #2


      That's pretty slick!

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