"David J" wrote in message
...

"j j" wrote in message
...
I have a question about leaving live wires inside walls
how can it be done safely?

we have an old house with lathe and plaster walls. it has rather old
wires.

when you say "old wires"
do you mean
knob and tube?

no, both hot and neutral (but no ground) are present in the same tube,
surrounded by some paper-type insulation. the outer cover seems a bit
"oily".
I think wires are still in decent condition, but I can't be sure, some might
be eaten up and brittle. as a result we avoid using large loads on these
wires and I'd like to add new outlets and leave the old wires in place
because they all come from the same source (one breaker shuts off half the
house) and I can't turn power off for them without replacing every wire and
breaking lots of walls.
so I want to leave power for the lights on the old wires and put outlets
with new wires.