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, and I won't have access to re-wire two rooms until I remodel them in the spring and there isn't any good way to get NM cable from those two rooms to the service box until the walls come down in a couple months.
Coincidentally, a friend of mine found a bunch of new old stock A-head connectors in a bag in his attic exactly like this one in my basement:
My understanding is that these are still allowable under NEC 300.16 and would give me an easy way to keep the 2 problem rooms live until I can finish replacing the circuit. Am I correct that this is still legit? If so, are there any issues with using NOS hardware for the splice? I don't really want to disturb the old wiring that I'm not immediately replacing any more than I have to, so this seems like a better solution than a junction box.
Best Answer
The article you need to refer to is 394.
Here is an excerpt that applies to your situation.
Many jurisdictions don't allow K & T unless it is a historical house. For your temporary situation, unless you are pulling a permit and getting inspected, extension of the existing system would seem reasonable.
You should replace it with a more modern grounded wiring method as soon as is practical though.
Happy New Year!