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bfordz
Feb 23, 2013, 07:45 PM
Is there or was there any rhyme or reason to the way they ran the knob and tube wiring? I've noticed the two wires don't always come from the same direction; e.g.. I installed a box for a wall sconce, one wire came from the attic the other from the floor (from above and below the light).

I'm remodeling our 2nd floor bath and insulating; our 3rd floor attic light switch w/K&T wiring is in one of those walls. I'd like to replace the wiring with new (so I can insulate) but that wiring is only the switch side.

Is there a logic I can use it figure out which direction the other wire is coming from? Do I have to just start following wires to where ever they lead me?

TIA

ma0641
Feb 23, 2013, 08:17 PM
It really isn't much different in today's wiring. In many cases, the wiring will run from the basement up to the outlets and then up the wall, into the ceiling and then down to the switches. They are typically installed to save wire.

bfordz
Feb 26, 2013, 09:14 PM
It really isn't much different in today's wiring. In many cases, the wiring will run from the basement up to the outlets and then up the wall, into the ceiling and then down to the switches. They are typically installed to save wire.

Thank You for the reply;

Is the 'hot' side still the switch side back then?

ma0641
Feb 26, 2013, 09:48 PM
Thank You for the reply;

Is the 'hot' side still the switch side back then?

The hot wire, usually black or red, is always the switched line, never the neutral. There is no real difference between Romex and knob and tube except that it is fabric covered and 2 wire. You can carry current to a switch on a white but it must be marked with black tape or a marker. Unfortunately, I find many unmarked switch loops.

bfordz
Feb 26, 2013, 10:24 PM
Thanks again for your explanations.