Old Work Box Problem

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"I'm not too concerned about the connectors."

I may be mistaking, but i heard two things that din't make sense, one was old MC cable, in an old home with lath and plaster finish, are you sure it's not old AC cable?
 
satcom said:
... are you sure it's not old AC cable?
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It certainly must be. I picked up on that too, but so many people use the term interchangably (albeit incorrectly). Realistically, the termination procedure is the same, regardless. I haven't seen a connector in quite some time that was only for type AC or only for type MC. Most connectors are dual rated nowadays.
 
jeff43222 said:
I'd be a little hesitant to use them in this case. The wires inside the MC are cloth-covered, and the insulation isn't in the best shape. I have a feeling things wouldn't fit too well, and I don't want to risk further damaging the insulation.

I think I'm going to go with the consensus and cut out one of the cross braces (the other one isn't in the way) and put in the fan spreader box.
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If the cable is very old I doubt that it is MC cable. It's more likely AC cable or as it's called around here BX.
 
I attempted to install the fan box, but it didn't turn out so well. I was able to get the cross support piece out OK, but the snag was trying to connect the four BX cables to the box. A couple of them were very short, and I wasn't able to connect everything and mount the box to the spreader bar. After a very long time trying, I realized it just wasn't possible.

So now my dilemma is what to do with the four BX cables. The HO is already resigned to not having her ceiling fan, but in the meantime I have a nice 4" hole in the ceiling and four loose BX cables spliced together with no box. I don't see how I can put them into a box, properly mount the box, and leave everything accessible. Anyone have any brilliant ideas?
 
I may not be visualizing the situation properly, but are you trying to come through the back of the box? Would it be possible to come through opposite sides of an octagon box? With a duplex connector on each of 2 sides? If so, you may be able to still use the spreader. And if you can't use spreader, you may be able to cut a notch in a 2x4 (so that box will sit flush with finish ceiling) and slip it up through the hole. Then screw to 2x4 up through plaster and lathe. Patch screw heads. Sort of home made old work box which spreads weight of box to plaster. Possibly even cover screw heads by using medallion. Using medallion would let you cut hole a little bigger if you need room to get duplex connectors in. But i'm visualizing you being able to put 2 bx's in one duplex. Then slide box into ceiling and away from other 2 cables in order to get them into connector. Then sliding it into place.

But maybe again I'm not seeing the whole picture. Or maybe cables are so short and in bad shape that you're screwed. Good luck.
 
Jeff, this may be a stretch (although not for me; I consider upper kitchen cabinets removeable), but every old-work fan box I've seen can be removed by simply reversing the installation process.

See where I'm heading? As I see it, a junction box could be installed above the fan box, with a cable with the required number of conductors (2 or 3) passing from that box to the fan box.

If you look at the NEC definition of accessible as pertaining to wiring methods, you can access such a junction box about as easily as you can the box on a recessed fixture.
 
As long as the wires are long enough to reach the hole in the ceiling you really should not have any problems, other than yes it is going to be a pain, Your going to have to use twin connectors, try 90o twins if nothing else... You can do it! :)
 
Thanks for the good suggestions.

I tried every combination of going in the back of the box, on opposite sides, using duplex connectors, etc., but ran into problems no matter what I did. Coming in on opposite sides didn't work because not all the cables were long enough to allow that, especially once the spreader bar was in the way. All four of the cables came from the same direction, so that complicated matters. The duplex connectors were also problematic because the old wires were old, brittle, and thick, so jamming them into the duplex connectors was "fun" and managed to cause futher damage to the insulation, forcing me to trim the armor off one of the cables just to expose some undamaged insulation. I like the 2x4 idea, but the main problem now is that the cables are pretty short and not in good shape.

Larry's idea of installing a j-box in the joist cavity and then tapping it for a new box is intriguing, but I'm cringing at the idea of mounting a deep j-box on the not-so-near joist by twisting my hand through the 4" hole and trying to connect four bx cables to it without causing further damage to the wire insulation. I guess the j-box would be theoretically accessible since the fan box would be removable without having to break anything. But I have a hard time imagining the recessed j-box idea would be feasible. Still, it's better than anything I came up with.

The one thing that would definitely work would be to open up the ceiling somewhat and connect the cables to a joist-mounted box. The only problem with that idea is that it will cost the HO even more money since she'd have to call my drywall guy to fix the damage I'd do.
 
Don't forget the possibility of a medallion. Celtic brought it up back at #8 post.

The medallion will be 12 to 16" in diameter, depending what you find or choose. It will be 1" to 1?" thick, so it will use up a lot of the 2-1/8" deep box you mentioned earlier, BUT, you can cut the 4" hole wider to permit the AC to come down to new ?" KOs punched in the sides of the octagon.
 
Ah. I read your post after I was done typing.

Medallion + 2x4 + 1900 or 11B.
 
I think moving enlarging the hole and covering it all up with a medallion might be the best plan, assuming the HO goes for it. I'm not generally a big fan of medallions, but the HOs I deal with seem generally more accepting of them.

If that doesn't work, I think Al's phone number might magically find its way into the HO's hands... :D
 
Where I live all structural lumber must be pressure treated. The spreader bar fan kits just don't get a good bite at all when the joist are pressure treated. I like the medallion idea, used lots but never thought about using one to make a larger hole and patch for adding a proper backing/ fan box. That is a good trick. Lots of times I use medalions to keep the light fixtures separated off of combustable ceilings like canik ones we have here on older houses.
 
Jeff - I'm staying tuned to this thread. Like to hear how you finalize it, and would love to see a pic or two.

Why not go with the JB as Larry has suggested, and what's wrong with getting the drywall guy it. It really sounds like the right thing to do. I just hope you gave the HO a heads-up that old work has it's risks. I always lay that out up front, and usually try to lay out a worst case scenario. That way, the owners not sitting there thinking - "boy did this guy turn this into a major fiasco". I've found by at least letting the HO know what could go wrong, is always best - and if things go smoothly you could look like a hero. Things go worst case, and at least you gave them the heads-up. With old wiring, and brittle insulation, I really would want to get things opened up, old armor stripped back and get the JB so you can see how everything goes back togehter. Then get you buddy the rocker in and fix it up right.

Brett
 
Jeff, me again. Thoughts:

When faced with crumbling insulation, I like to remove as much of it as I can and slide the appropriate color of insulation stripped form a piece of one-size-up NM onto the wire, sliding it as far onto the wire as possible.

Also, if you enlarge a hole, make a J-box, and patch over it, you might be rendering the box inaccessible, unless you use this method to bring the cables directly into your fan box.

Since all of the cables come from one direction, you can "gain" as much cable as you need by moving the box over that many inches, and then patching the ceiling.
 
My DIY nature will show in this post :)

When I lived in Massachusetts, I lived in an old house that was built without much electrical (I think that there may have been K+T, but it was replaced) and all of the wiring was done with fished BX. Plaster and Lathe, crumbling insulation, the works.

I would cut in a new junction box separate from the fan box, and simply use a blanked off cover painted to match the ceiling. Not pretty, but almost invisible (how many people stare at the ceiling) and this will let you deal with fan support and only a single cable. This way you can use a large box for the old BX, and will let you get extra cable length and have lots of room for knockouts.

Once the insulation starts crumbling, you are fighting a loosing battle, better to cut it back to the point where the cable is simply sound and not damaged by heat.

When dealing with the crumbling insulation, I like to use silicone insulated fiberglass sleeving. The material is overkill in terms of what house wiring requires, but it is nice and stretchy and easy to work over the old insulation, and nice and sturdy once in place. I get it in small quantities from McMaster.

-Jon
 
you just have to battle through it. I had the same situation in my house. if they are old BX wires be very carefull because the insulation will crack right off them youll really be in a mess. try using two double bx connectors or a few 90 bx connectors. if cracking becomes a real problem try using some heat shrink tubbing. if you break out one set of cross braces Im willing to bet the farm that the house will be just fine, barring that it has no problems to begin with.
 
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Tony - with crumbling linsulation, I'd be very nervous about using 90 degree connectors - this implies some very tight bends in the wire to get through that connector.

I agree with Winnie - how many people look up at the ceiling - a nice blank plate setting the box so the cover falls flush with the surface of the ceiling. If people are looking up at the ceiling, chances are you're boring them.:)


Brett
 
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