K & T wiring

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I've seen old houses where all circuits enter the breaker box as cables, but some rooms still have knob-and-tube wiring. (A homeowner who needed to upgrade wiring for his kitchen may have found the old wiring adequate in a bedroom.)
That leads to a question that didn't occur to me before. Was there a proper way to connect K & T to a cable?
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On 5/31/2010 1:50 PM J Burns spake thus:

There was, and I *think*(TM)(R) it simply involved making splices using approved methods (like Western Union splices) and covering them with insulating tape. I don't think such connections had to be inside a junction box, as they would today.
But I could be wrong.
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Originally, the K&T would have entered the fuse panel through screw in ceramic insulators. When that panel was replaced they probably ran a piece of BX cable to a junction box, and ran the K&T insulators into knockouts in the J box, then either spliced with wire nuts or solder depending upon when it was done. Here is a picture of an old K&T fuse box. Notice the fused neutrals:
http://i17.photobucket.com/albums/b97/royapples/Old%20hause%20renovation/originalturnofcenturyKTfuseboxlocat.jpg
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RBM wrote:

http://i17.photobucket.com/albums/b97/royapples/Old%20hause%20renovation/originalturnofcenturyKTfuseboxlocat.jpg

Thanks. Comments by others are interesting, too.
In the 1980s, my parents moved into a house where they wanted grounded outlets, more outlets, and fluorescent lights. Cables went from the breaker box to junction boxes in the attic, but much of the lighting was on K&T.
Instead of making connections to K&T, I was removing it. I wasn't aware that the insulation was unreliable, so I didn't think about how the electrician who had installed the junction boxes had made safe connections to existing K&T.
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J Burns wrote:

The K&T I have run across has insulation that is in good condition after all these years. The exception is at light fixtures, where the heat of the lamp, or especially a ballast, has raised the electrical insulation temperature far beyond what was intended. The same problem happens with BX, and other wiring.
K&T is actually still in the NEC (article 394 - with very limited use) and is intended to be concealed (some exceptions in attics).
The refeed I have seen is to put a j-box near the knobs and run wires into a box with "loom" over the wire from the knob to inside the box. RBM's picture show loom. I have seen the loom just go through a knockout (preferable both wires through the same knockout). The K&T is spliced inside the box to Romex, or some other wiring system.
--
bud--

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with K&T concealed in walls how can you be CERTAIN its in good shape? theres no way to see it unless you open the wall, and once you do you might as well just replace the K&T
I helped gut a friends fire damaged home. It was amazing the bad wiring I found in the walls.
The owners finally agreed to a complete rewire.
the fire wasnt electrical, a cat knocked over a lamp the damage to the home 135,000 exceeded the homes value by far.
sadly their old homeowners insurance had been canceled when their insurer went out of business. K&T, bad roof, broken sidewalks etc etc. they had forced place insurance on structure only, and lost much of their possesions
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with K&T concealed in walls how can you be CERTAIN its in good shape? theres no way to see it unless you open the wall, and once you do you might as well just replace the K&T
I helped gut a friends fire damaged home. It was amazing the bad wiring I found in the walls.
The owners finally agreed to a complete rewire.
the fire wasnt electrical, a cat knocked over a lamp the damage to the home 135,000 exceeded the homes value by far.
sadly their old homeowners insurance had been canceled when their insurer went out of business. K&T, bad roof, broken sidewalks etc etc. they had forced place insurance on structure only, and lost much of their possesions
You know it's in good shape the same way you'd know if Romex is in good shape. There are no open, or flickering circuits. K&T has no less integrity than NM, and at least it's mounted on insulators, and whenever it passes through wooden framing it goes through ceramic insulators
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oh yes and connections are exposed. so the connection begins overheating just a little and gets worse over time.
one day the connection comes apart and sparks.perhaps just dust from a 100 year old home starts a smoldering fire
Machines I fix for a living do this all the time, melt holes in side covers etc.
my problem with K&T is the lack of boxes
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oh yes and connections are exposed. so the connection begins overheating just a little and gets worse over time.
one day the connection comes apart and sparks.perhaps just dust from a 100 year old home starts a smoldering fire
Machines I fix for a living do this all the time, melt holes in side covers etc.
my problem with K&T is the lack of boxes
If splices come loose, regardless if they're inside boxes, or suspended on insulators, everything on the circuit flickers, and becomes apparent to the user, that a problem exists. Typically, a loose connection becomes an open connection, and no longer heats.A connection is not going to overheat unless it's loose, or overloaded.
I get it, every best friend, neighbor, uncle, nephew, etc. you have, has had a disaster of some sort caused by K&T. It's more likely that you should stop helping your aquaintenances with their wiring problems
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.

yep attack the person when shown the truth, since you cant discredit the solid info i posted
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I don't think that Hallerb empirical evidence would constitute "solid info" in anybody's book.
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On 6/3/2010 5:17 PM RBM spake thus:

Of course it doesn't.
I a lot of direct experience working on houses with knob & tube wiring. With no exceptions, it is in perfectly safe and serviceable shape.
It is, of course, possible that somewhere there are houses with problematic K&T wiring, and the hallerb had a bad experience with one. That in no way negates the overwhelming majority of houses that have perfectly intact K&T. So we can safely ignore his ravings and rantings.
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Are there any old timers out there who know TWO ways to wire a 3-way switch using the K&T way? I once won a sizeable bet from a PhD that it can be done.
Nonny
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There are several ways to wire a 3 way switch system, each slightly different depending upon where the feed is located, and where the load wires are located, however, I think since you're asking "old timers", you are probably thinking of a "Carter 3 way" circuit, which was commonly used in the early 20th century
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ultimately at home resale time it doesnt matter what anyones opinion of K&T is.
Other than the buyer, home inspector, and perspective homeowners insurance company.
Just like main fuse panels, generally to get homeowners today they must be upgraded for circuit breakers
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On 6/4/2010 8:15 AM, snipped-for-privacy@aol.com wrote:

Again, just not true.
--
Steve Barker
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yeah despite posters reporting this here....... not me.
for people just reading this call a agent not your own and ask.
or wander in and ask any agency.
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On 6/5/2010 8:07 AM, snipped-for-privacy@aol.com wrote:

this reminds me of a peanuts cartoon when the adults are talking. All i hear is "blah blah blah blah"
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snipped-for-privacy@aol.com wrote:

Anecdotal evidence, which is all you ever come up with, proves nothing. Anecdotal evidence shows astrology and homeopathy work.
If K&T is as dangerous as you say where is the actuarial data?
About your only source I remember is from a group that replaced some K&T, left most of it, and insulated over what was left. And that was in your own state.
Your hysteria doesn't count, on K&T or anything else.
--
bud--

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bud-- wrote:

The house my grandfather owned has a pair of light switches inside the front door. They still work fine after nearly 90 years. By coincidence my other grandfather, 1,000 miles away, invented those switches.
I might want to replace the K&T to the two ceiling lights but not to the switches. (It's an exterior wall, and anyway I don't want to tamper with the switches.)
Using "loom" to run K&T into a j-box could be just the thing for me. I imagine the material shouldn't crumble or support a flame. Where could I find loom material?
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