What type of electrical box do you use for smoke alarms?

Old 03-15-14, 10:56 PM
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What type of electrical box do you use for smoke alarms?

I am mounting a smoke alarm to the ceiling and just want to make sure the pre-wiring is done right. What type of electrical box do you use for mounting a smoke alarm? A rectangular one, round one, or something else?
Old 03-15-14, 11:55 PM
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All mine are on round boxes. I imagine the mounting plate would fit either though. IIRC they have multiple holes...but since smokes are round...thats what I'd go with.
Old 03-16-14, 05:39 AM
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I would suggest a ceiling box, round or octagon, not a switch box. Octagon is the most common, round second. Rectangle I'm guessing refers to switch boxes. Switch boxes use 6-32 fixture screws and are used most often in walls for switches and receptacles. They may not have enough capacity for the wire count if more then two 3-conductor cables . Ceiling boxes use 8-32 fixture screws and have greater capacity then standard depth switch boxes.
Old 03-16-14, 06:06 AM
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Either box shape can be used for smokes. The important thing is the box capacity. Make sure it is large enough.
Old 03-16-14, 10:19 AM
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Plastic boxes work particularly well and are easy to use.

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