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Questions tagged [knob-and-tube]

For questions about Knob and Tube electrical wiring throughout the home. Sometimes abbreviated as K&T.

0
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1answer
18 views

Adding a vanity light to a switched knob and tube ceiling light

I shut off the main breaker, disconnected an ancient light fixture, taped new wire to the existing knob and tube and pulled it all up into my attic. Next I pigtailed from the K&T to two new (WBG) ...
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2answers
46 views

Replace 6 fuses with 2 breakers?

I hired an electrician replace my old 6 fuse subpanel with breakers at an existing newer subpanel. I thought I’d get wires running from each circuit to a new breaker, but all he did was wire the six ...
1
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3answers
135 views

Understanding my main box for Knob and Tube wiring

I'm trying to map all my circuits and prepare for replacing my knob and tube wiring. I have three boxes and when testing voltage I notice my central white wire isn't hot. I expect this to be the ...
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1answer
57 views

Knob and tube wiring

I'm currently remodeling my 1876 home. Some upgrades have been made by just adding new breakers and wiring, but I've come to a room that runs its power through the old knob and tube wiring. I am going ...
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0answers
64 views

Knob and tube - cap red wire on light switch?

I have a house that was built in 1913 and it still has knob and tube wiring. I recently bought a Wemo dimmer light switch that has 4 wires (red - load, white - neutral, black - line, and green - ...
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1answer
77 views

Non-metallic cable in Knob and Tube Boxes

Does NEC specifically prohibit NM cable in an old K&T switch box? I need to do the calculations, but I think I have room as I'm just terminating a 12/2 cable to a receptacle (K&T removed from ...
1
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1answer
38 views

how to replace surface conduit for a two-wire lighting circuit?

I have an old house with unswitched knob-and-tube running to a ceiling fixture. Previous owners ran surface conduit to a wall switch and to a second light fixture over the sink; none of this was ...
6
votes
4answers
962 views

In knob and tube wiring, how to identify neutral wire vs a dead wire?

I'm in the US, Ohio if that matters. I have an old house with many circuits still on K&T wiring. I haven't been able to find information on how to identify a neutral wire - most guides just tell ...
2
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3answers
110 views

Why does Knob and Tube need an air gap?

I know that knob and tube wiring needs an air gap to dissipate heat. I know that modern sheathed cable does not need an air gap. I know both are made of copper, one is grounded, one not. So why does ...
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2answers
83 views

What should I do about an electrical service panel that is next to the gas service meter?

I have to upgrade my electrical service panel from knob & tube to current grounded code. The house is on bedrock and ground is the water pipe entry in the garage more than thirty feet away. Now it ...
3
votes
1answer
99 views

Identifying Knob-and-Tube

My parents recently purchased a mid-1920s house and are doing some work on it as a retirement home. We had an electrician out to the house the other day; upon peering behind one of the outlets, he ...
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1answer
188 views

How to identify a fixture/outlet and wiring to breaker as knob and tube?

I have spent time charting out all the lights, outlets, etc. in our house and what breaker they are each on. I know that most of the original part of our house in knob and tube and the early 90's ...
6
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3answers
1k views

Leaving lost neutral wire

I am in the process of clearing out old random wires from my 100 year old house (think multiple layers, modern, knob and tube and everything in between). In the process of doing this, I tried to ...
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3answers
2k views

Test outlets to see if knob and tube? (grounded?)

Considering a rewire in the future and want to figure out which outlets (and ideally fixtures) are knob and tube. I know many are, some are not. Probably all 2 prong outlets are k&t, possible some ...
3
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5answers
1k views

Electrical: Is this tangle of wires in a 100 year old house cause for concern?

Just bought a 100 year old house and it has knob and tube wiring along with newer wiring running to the kitchen and parts of the finished basement. There's a whole bunch of wires in the basement. I'm ...
4
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3answers
1k views

Remove a light switch to an outlet - knob and tube

I have an outlet with a light switch that currently controls it. What I would like to do is remove the switch so the outlet is always hot. I considered just removing the switch and connecting the ...
1
vote
1answer
91 views

Low amp power breaker strip or reciptical adapter for knob and tube homes during rennovation

we are renovating our home room by room. We have been working on electrical, but the top and 3rd floor been delayed due to, well, pure time vs time with then new baby. So the thing about this home is ...
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1answer
1k views

How can I tell if an appliance is grounded?

We're doing some kitchen remodeling in our 100-year-old home and came across some very sketchy wiring hidden in the soffit. There is never any current running through the junction, and because there ...
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0answers
97 views

Can we remove this wiring - just one wire tied together?

I just removed my kitchen soffit and found suspect wiring inside. It's a 100-year-old house with mostly knob and tube, but the kitchen was redone in the early 90s. Going through the house flipping on ...
0
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1answer
337 views

Outlets worked intermittently with voltage fluctuations and are now dead entirely

Just bought a home built in the 1920's, the knob-and-tube was updated a couple times at different eras but there is still fabric wrapped ungrounded wiring (FWUW) in many rooms. The living room (and ...
1
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0answers
82 views

Electrical current in walls

I have an older house, from the mid 20s. Most of the wiring is knob and tube. Since there are brick walls every time i want to hang something I drill a hole for a screw. To avoid electrocuting myself ...
1
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2answers
478 views

Does MA require permit to replace old K&T and if no how do I know if work is done to code?

Is it required to pull a permit in MA to replace knob and tube wiring? If no, how can one determine if the work done adheres the the proper codes? Who should be sought after to confirm this if no ...
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1answer
85 views

Why must all outlets share a ground conduit?

I was reading this answer in my quest to see how possible adding grounds to my existing knob and tube house would be, and was suprised by: Are you asking if it's OK to run a separate ground wire ...
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2answers
395 views

Are the old A-head terminals for connecting to knob and tube wiring still compliant?

I'm in the process of decommissioning the last active (hopefully) knob and tube circuit in my house (I'm in the U.S.). The problem is that about 90% of the lighting in the house is on this circuit, ...
3
votes
2answers
174 views

How to minimize wall tearing when installing new wiring?

We have bought a new house with knob and tube wiring. We are now looking into replacing all of it with new wiring and understand that significant wall-surgery will be required to run the conduits. ...
4
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3answers
361 views

Why are ungrounded GFCIs required to be labeled?

I discovered in my new house that someone had incorrectly connected grounded outlets (without any ground connected) to the knob and tube wiring. I have read that the outlets can be made safe by ...
4
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4answers
2k views

Box in knob and tube wiring between ceiling and cellulose?

I know that code says no cellulose insulation with knob and tube wiring because of possible heat build up. I also know that evidence of it causing fires because of this is scarce and a few states ...
3
votes
1answer
350 views

what causes a ceiling fan light to blink

I dropped a new romex line down through the wall to provide power to a flat panel tv mounted on the wall. The wall has K&T wiring in it. Everything seemed fine, until I noticed that the lights in ...
1
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2answers
221 views

Running conduit near knob and tube wiring

I have some new AC ducts in our new house that will soon be concealed behind new drywall, but before the drywall goes up, I wanted to run some conduit from the upper floor down to the basement for ...
3
votes
2answers
10k views

Is it safe to put insulation next to knob & tube wiring?

I have a room that has some really ugly cheap panelling on the walls. I want to rip it out & replace with drywall. While I'm at it, I'd like to add soundproofing insulation between rooms & ...
1
vote
1answer
486 views

Integrating into knob-and-tube wiring: okay to borrow a ground [duplicate]

I have a mixture of knob-and-tube and NM-B. If I'm extending from knob and tube, but I have a (different) an NM-B circuit nearby, is it technically allowable to ground via ground wire in the other ...
9
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5answers
16k views

Should I use a GFCI or AFCI circuit breaker with knob and tube wiring?

My American house was built in 1942, and much of the wiring is still knob-and-tube wiring (2-wire, no ground). Over the years new modern wiring has been added to the house, but we still have some KnT ...
3
votes
1answer
1k views

Can a Knob & Tube live hot wire be left disconnected without the neutral in a switch box?

Can a live (capped) knob & tube hot wire be left disconnected, without the neutral (it's removed) in a new switch box now fed by a modern 20amp circuit and romex? The reason it is still live is ...
5
votes
4answers
45k views

How can I attach modern fixture to knob & tube wiring?

I have a modern external light fixture that needs to be attached to an existing exterior electrical 'box'. The older parts of the house have knob & tube wiring and there is evidence of gas ...
12
votes
2answers
9k views

Can disconnected knob-and-tube wiring be left in place?

The house I recently bought (over 100 years old) has had almost all of its wiring replaced with a new elctrical board. However, in two cases the new wiring has been connected to existing knob-and-tube ...
3
votes
1answer
4k views

How to determine what 3-way switch system was used?

How can I tell if an old Knob & Tube 3-way switch is still legal by the modern NEC? Specifically I am trying to tell if my switch is a "California 3-way" (or "Coast 3-way", "Hollywood 3-way", etc....
5
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2answers
3k views

I am removing some Knob and Tube wiring. Can I leave the NEUTRAL wires hanging in the walls?

I am renovating my bathroom. I am bringing in new circuits for all the electrical, and replacing the boxes. I will have no problem capping off/removing the live (black) knob and tube wires in boxes. ...
7
votes
4answers
23k views

Can I replace an outlet that uses knob and tube wiring with a grounded outlet?

Can I replace an outlet that uses knob and tube wiring with a grounded outlet? Obviously the best choice would be to replace the old wiring. Is there a standard way to ground these outlets? Do I need ...
12
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3answers
2k views

What is “knob and tube wiring”?

I assume this is some USA wiring system, am I right?
37
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10answers
53k views

Should old knob and tube wiring be replaced?

I have been doing some electrical work in my house and I noticed it has old knob and tube wiring that is still hot, should this be replaced as found or is it fine to just leave it? It seems really ...