cloth covered wiring

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romex jockey said:
In my state, a formal complaint can be forwarded>>>
https://firesafety.vermont.gov/sites/firesafety/files/files/forms/dfs_complaintform.pdf
I would encourage that you inquire as to similar doc's on your turf
;)
~RJ~
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That's excellent advice, if such a thing does exist where you live.

Aside from possible self-protection (liability-mitigation), you'd be taking an active step to protect the occupants, regardless of short-sighted owners or landlords.

BTW, the form includes this checkbox:
ELECTRICAL HAZARD (extension cords in use)
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I'm imagining the loud knock on the door, lights flashing outside, and the grim fire martial, "We've received a report...."
 
BX is generally the worst old wiring I have worked with. I have rarely been able to cut and strip it without scoring the insulation of the conductors. It may have been good when new but it didn't age well at all. I have seen a little of it with a ground but not with most.

I replace it wherever possible. Nothing good about it.
 
Agreed, old BX with cloth and rubber insulated conductors is the single most dangerous wiring method in existence. It's far more dangerous than K&T or ungrounded first generation romex. It needs to be 100% replaced. I've had a similar experience where a short circuit on a BX wired circuit caused a huge arc flash and burned the wall as a result. I would not sleep well in a house with that danger lurking behind walls.

I would not touch a house with BX unless it was a total rewire. It's either going or I'm not working on it.
 
peter d said:
Agreed, old BX with cloth and rubber insulated conductors is the single most dangerous wiring method in existence. ...
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That's interesting and counter-intuitive. Enclosing the conductors in steel would seem to make it more safe, not less. (yes, I did read the previous posts in this thread)

I wonder if it was less of a problem when it was popular for new installations, (which was when, 1930-1960?) when available fault currents weren't as high and panels had fuses -- which would have been somewhat current-limiting, even if the "current limiting" concept hadn't emerged yet?
 
drcampbell said:
That's interesting and counter-intuitive. Enclosing the conductors in steel would seem to make it more safe, not less.
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Certainly enclosing conductors in a continuous steel jacket, with a low-resistance path to ground, makes all the sense in the world.

By contrast, enclosing live conductors in a spiral of steel, with a few-ohms of resistance between a fault and the panel, is a lovely way to save on light bulbs. Just enjoy that orange glow from the BX armor.

peter d said:
Agreed, old BX with cloth and rubber insulated conductors is the single most dangerous wiring method in existence. It's far more dangerous than K&T.
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'Zactly. And yet it's knob & tube that gets all the bad press, and all the unpleasant attention from insurers & home inspectors.

There's no justice.

I would not touch a house with BX unless it was a total rewire. It's either going or I'm not working on it.
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Now that's the kind of intolerant attitude that I can respect. Hear hear!
 
drcampbell said:
I wonder if it was less of a problem when it was popular for new installations, (which was when, 1930-1960?)
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My house was built, and wired with BX, in 1934. I'm sure it was much less frightening to behold then, and for the first few decades thereafter, than it was in 2015.

One advantage of the old stuff: no need for wire strippers. Just flick your fingernail against the desiccated rubber insulation (wrapped with brittle cloth) and you've got naked conductors.

The ravages of time, weather, and ozone were magnified by the high-temperature luminaires that were installed mid- or late-century. And by the pure lack of junction boxes.
 
drcampbell said:
That's interesting and counter-intuitive. Enclosing the conductors in steel would seem to make it more safe, not less. (yes, I did read the previous posts in this thread)

I wonder if it was less of a problem when it was popular for new installations, (which was when, 1930-1960?) when available fault currents weren't as high and panels had fuses -- which would have been somewhat current-limiting, even if the "current limiting" concept hadn't emerged yet?
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Current limiting of the sheath was the problem, it has high enough resistance because it is one long piece of steel, that spirally wraps around the conductors it contains. The less resistance it has the more ground fault current can flow and open the overcurrent device faster, and the reason newer AC cable has a bonding wire under the sheath now.
 
When dealing with insulation falling off of the wires, I try to remove all I can, even into the sheath, and slip a length of the correct color of insulation stripped from modern NM onto the wire.

If you measure it carefully, or trim it after you slide or twist it onto the bare wire, the splice will keep it fully on the wire. Sometimes, you need to use insulation from wire one size larger.
 
kwired said:
. . . and the reason newer AC cable has a bonding wire under the sheath now.
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Correct. The bonding wire is not an end-to-end equipment grounding conductor, it is a turn-to-turn shorting wire. That's why it is effective despite its relatively small equivalent gauge.
 
peter d said:
Agreed, old BX with cloth and rubber insulated conductors is the single most dangerous wiring method in existence. It's far more dangerous than K&T or ungrounded first generation romex. It needs to be 100% replaced. I've had a similar experience where a short circuit on a BX wired circuit caused a huge arc flash and burned the wall as a result. I would not sleep well in a house with that danger lurking behind walls.

I would not touch a house with BX unless it was a total rewire. It's either going or I'm not working on it.
Click to expand...

drcampbell said:
That's interesting and counter-intuitive. Enclosing the conductors in steel would seem to make it more safe, not less. (yes, I did read the previous posts in this thread)

I wonder if it was less of a problem when it was popular for new installations, (which was when, 1930-1960?) when available fault currents weren't as high and panels had fuses -- which would have been somewhat current-limiting, even if the "current limiting" concept hadn't emerged yet?
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Enclosing in steel is actually part of the problem. I've usually not been able to cut BX with a rotosplitter, have to score with a hacksaw and twist to break. That bit of twisting is enough to damage conductor insulation, which is nearly always brittle to begin with. I'm all in favor of fixing what can be fixed but it's time for BX to be laid to rest. Save some for the museum (do we have one?) but scrap the rest.
 
LarryFine said:
When dealing with insulation falling off of the wires, I try to remove all I can, even into the sheath, and slip a length of the correct color of insulation stripped from modern NM onto the wire.

If you measure it carefully, or trim it after you slide or twist it onto the bare wire, the splice will keep it fully on the wire. Sometimes, you need to use insulation from wire one size larger.
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Is that post sarcasm or serious? I cannot tell. Either way, where is the added step to keep it all in place by filling he end with RTV?
 
LarryFine said:
Serious. What made you think otherwise? :?
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Admit to doing same in my mother's 120 YO house for a temp fix, but replaced run later.

Thinking 'not serious' in context of the previous few comments on liability, code, AHJ, etc.
Not being a code expert, wonder what section addresses that type corrective action?
 
I too use heat shrink to cover those damaged conductors. 600 volts per layer rating is good enough for me. But for abrasion resistance sometimes I use more layers if I see an issue in the box. Larry's use of new insulation covers the abrasion issue.

Glad I sold dad's BX wired house 10 years ago! :D
 
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