Electrical – 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 old and brittle, so I'm a little concerned.

Best Answer

The advice my family once got from an electrician on this question was that if you have low amperage service and NEVER touch it, you're probably okay. If you have regular electrical service or touch the circuits at all, remove ALL of it. His basic theory was that if you keep the wires cool, and they haven't caused you trouble yet, it's unlikely to cause a problem. Granted that advice was about 15 years ago and none of that wiring is improving with age.

Once you touch the lines at all, rip it all out. It's very likely that you will introduce a problem between the coating and the wire. The house we were dealing with went another 10 years before we needed to rewire one of the old circuits. Once that happened we rewired the entire house all at once.

If you're concerned at all, turn off the affected circuits, and get rid of it. Better safe than sorry on this one.