Smart Box?

mrFinpgh

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Oct 30, 2015
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Wondering if anyone else has ever used the side-mount Smart Box ceiling fan box from Madison Electric?

I've got a ceiling composed of drywall over plaster and lath.  The old pan was nailed offset to a joist.  Knob and tube lines feeding into the device, both on one side of the joist.

Originally, I was going to use a 1.5" deep box screwed to the joist, but I need to have two separate knockouts to run the knob and tube lines through.  Those boxes only have one knockout per side of the joist. 

I think the Smart Box has a lot of openings for feeding wires, so I should be able to handle my feed issues that way, but I want to make sure that it will work with a very thick ceiling without being recessed.  Hoping someone else on here can speak to that one way or another.

Thanks,
Adam

 
I've never used one, did look at it on line. I'd suggest finding one, measure from bottom edge to where the screws exit the box. If your ceiling thickness is equal to or less than that number it should work. Per the NEC the box can be 1/8" recessed from the face of the drywall.

Are the conductors really knob and tube still?

Tom
 
Thanks, Tom.

Yep - it's an old rowhouse.  When I bought it, it still had a 60amp service, glass fuses, and most of the house was on one knob and tube circuit.  I've since reduced the amount of devices on that circuit to 3 light fixtures and two outlets and have LED fixtures to keep the draw down even more.  None of the electricians I've had over think it's worth rewiring based on the current condition.

I haven't been able to find a local carrier of it, so I'm going to give Platt a call and see if they know.  Definitely don't want a fan falling on me while I sleep!

-Adam

 
Hi JD,

I don't know.  I like that it has the separate knockouts.  Wondering if it's fan rated, though.

-Adam
 
Hey Tom,

I've got one of those sitting on the window-sill in the room.  Along with three other boxes.  Not sure I could make it work.  The current hole is right next to the joist.  I can cut a new hole, but it would have to be close enough to the one there now so that I can run the conductors into the box.  Only other time I used one of those, I had it pretty centered.  I assume it can be offset to one side?

The worst thing about this whole endeavor is the loose mineral wool insulation from 1934 that's above the ceiling.  It falls all over and makes my skin glow bright red. I need a stent that I can stick in there to keep the insulation from falling on me!

Platt measured one of the Smart Boxes for me :  lower screws come out at 1.5", upper screw comes out at 2 1/8".  I'd say I'm around 1.25" from the ceiling to the joist (hard to measure exactly with the pancake box in there).  If I recessed the box about 1/8" from the face of the drywall, that would give me 3/8" to work with.  Would there be any structural benefit to adding more material under the joist?  I figure I've got 1.25" of space to work with there.  [wink]

Thanks,
Adam

 
If you can get all the screws into the joists is see no benefit to adding the additional material.

Tom
 
I ordered one, so I'll follow up on how it goes.  It looks good from the images.

Now I just need to strip some romex sheathing to slide over the k+t conductors.  :-)

 
Following up on the smart box.

It arrived, and I installed it.  Pretty easy to use and feels extremely sturdy.  3 2" screws through a true 2x joist will do that.  :-)

One issue with plastic boxes and knob and tube is that the romex clamps are a little too aggressive for the wiring. The old knob and tube installations typically have the conductors just running through individual knockouts.  What I do is knock out the cable clamp and wrap some romex sheathing around the wire where it enters the box.

Then I'll wrap some tape around that to keep it in place.  This helps to cut down on the risk of abrasion and provides a little extra protection.  I suppose some friction tape would also be a good idea to keep the wires from wiggling around too much.  I might revisit that before I put the fan up.  I'll have an electrician out to deal with some strange stuff I can't figure out in the closet, so maybe he'll sell me a couple feet of it.  :-)

I did need to pick up an extended 5/16th nut driver to get the screws fully seated, but other than it looks like it will do the trick.

-Adam
 
mrFinpgh said:
Following up on the smart box.

It arrived, and I installed it.  Pretty easy to use and feels extremely sturdy.  3 2" screws through a true 2x joist will do that.  :-)

One issue with plastic boxes and knob and tube is that the romex clamps are a little too aggressive for the wiring. The old knob and tube installations typically have the conductors just running through individual knockouts.  What I do is knock out the cable clamp and wrap some romex sheathing around the wire where it enters the box.

Then I'll wrap some tape around that to keep it in place.  This helps to cut down on the risk of abrasion and provides a little extra protection.  I suppose some friction tape would also be a good idea to keep the wires from wiggling around too much.  I might revisit that before I put the fan up.  I'll have an electrician out to deal with some strange stuff I can't figure out in the closet, so maybe he'll sell me a couple feet of it.  :-)

I did need to pick up an extended 5/16th nut driver to get the screws fully seated, but other than it looks like it will do the trick.

-Adam

[member=59039]mrFinpgh[/member]
If you are having an electrician out for other stuff, why not have them look at or do the installation of the fan box?  That way you'll know it's done in a proper, safe manner.

Mike A.
 
He'll see it :-)

I'm pretty confident with simple device box wiring, but I do tend to leave them open until a pro has come by.

-Adam
 
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