knob and tube removal

[Matthew Barnicle]

Am I correct that all knob and tube is required to be removed at time of replacement? Does anyone have a code reference for this? Inspected a house today that had abandoned k&t still in place, It was replaced about a year ago, and I am thinking the electrical contractor that did the work might be required to come back and remove it. Thanks.

[Scott Patterson]

Am I correct that all knob and tube is required to be removed at time of replacement? Does anyone have a code reference for this? Inspected a house today that had abandoned k&t still in place, It was replaced about a year ago, and I am thinking the electrical contractor that did the work might be required to come back and remove it. Thanks.

I'm not aware of any requirement. Yes, it would be nice but you could never get rid of it all unless you tear out he walls, etc.

What would it hurt if it is left in place? I see nothing wrong if it is not live and has been replaced modern NM lines..

[Mike Schulz]

Maybe cut the exposed wires off so it's not a tripping hazard in the attic. Mice like to use them to slice there cheese. :p

[Matthew Barnicle]

If left in place, you could not determine if it was all deactivated during a cursory home inspection. Clipped wires everywhere with no junction boxes or wire caps. You can only do a sampling with a voltage sniffer, so no way to know if it is all deactivated or maybe some of it was left on a switch even if it is dead. Maybe insurance companies want it all gone. With the price of copper these days, you would think the electrician would be glad to remove it.

[James Duffin]

It seems like if you could see it to remove then there would not be a problem with the K&T being covered....it would be uncovered.

[Gunnar Alquist]

I tend to agree with Matthew. If present, I note that I cannot verify if all of the K&T has been disconnected/abandoned.

[Jerry Peck]

No requirement to remove it when abandoned ... which makes it oh so easy for a DIYselfer to re-energize it later ... with potentially deadly results.

[Randy Clayton]

I dont know of any requirement of removal; but was quite surprised that if it was installed correctly is ok by the code check manuals!! See the back of the book they have pics and everything.

[Scott Patterson]

I dont know of any requirement of removal; but was quite surprised that if it was installed correctly is ok by the code check manuals!! See the back of the book they have pics and everything.

FYI, Douglas Hansen has K&T in his home, if I recall it is in his kitchen area!

[Randy Clayton]

Scott, you know the last three homes I've inspected that knob & tube wire was replaced there was always one circuit usually the front porch still with the original wire????

[John Steinke]

There is no such code requirement. While there are code requirements to remove abandoned data, phone, and CATV wires ... there is no general requirement for removing abandoned power wiring.

[Gunnar Alquist]

There is no such code requirement. While there are code requirements to remove abandoned data, phone, and CATV wires ... there is no general requirement for removing abandoned power wiring.

No kidding? Why would that be?

[Jerry Peck]

There is no such code requirement. While there are code requirements to remove abandoned data, phone, and CATV wires ... there is no general requirement for removing abandoned power wiring.


No kidding? Why would that be?

Actually, John is mostly correct about that, but the alternative is to label those for future use rather than abandon them.

It is quite easy to mix up Class II wires and use them for other uses/systems/etc., so the accessible portion is to be removed. Yeah, its never done. :)

From the NEC.
- 725.25 Abandoned Cables.
- - The accessible portion of abandoned Class 2, Class 3, and PLTC cables shall be removed. Where cables are identified for future use with a tag, the tag shall be of sufficient durability to withstand the environment involved.