placement of junction box in attic for new light


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Old 06-12-24, 06:57 PM
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placement of junction box in attic for new light

When adding wiring in an attic for a newly installed light fixture, should junction boxes be attached to the top of a joist, or to the side of a joist? Putting them on top of joists makes more sense to me.
 
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Old 06-12-24, 10:50 PM
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I would go side of the joist, since that's what I'm used to installing stuff where sheetrock is going to be added. Additionally, that saves a little bit of ceiling height for you, if that matters.
 
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Old 06-13-24, 05:29 AM
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I've seen it done both ways. Not sure if this is a code issue or not. I think it would depend on how the space is going to be used. Boxes on the top could interfere with moving around the space but would be easier to install and wire up.
 
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Old 06-13-24, 05:53 AM
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I use a scrap of lumber attached to the joist, standing vertically. I attach the electrical box to the top. The scrap of wood acts as a mounting post to keep the electrical box exposed above any insulation and makes it easy to locate for anyone quickly looking in the attic.
 
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Old 07-06-24, 06:59 PM
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The junction box I had to work with looks like the one in the photo below. It came with 2 screws sticking out on the bottom side. So, I could not attach them to the side of a joist. I decided to attach them to the top side since those screws were spaced far enough apart for them to straddle the narrow side of a joist.


 
 

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