Which would you rather see in a basement for wiring? Old BX or new
Romex? I'm really not sure which should be preferable. BX has cloth
covered insulators and just the little strip for ground, but it is
working well (was working on a switch hot and accidentally touched the
box, the lights were off almost simultaneously with the spark - woops.
Just for the record I was wearing my work boots and was careful not to
let my hands touch anything metal; I just didn't realize that the switch
I was using was almost as wide as a single gang box...) cloth covered
insulation appears to be in good shape. I like the damage resistance of
the BX, but I also like the higher temperature rating of the new NM-B.

I'm certain that the old cloth had a 60C temperature rating if any; new
NM-B has 90C. Does it really make a big difference? I know the right
answer to the question is "use new BX with 90C insulation and a separate
ground wire" but... um... you priced BX lately? I am definitely
replacing a few runs with romex to allow for a 3-way switch on the
stairwell light and will be replacing a couple lampholders with shop
lights (cheap 'n' sleazy, just using short fixture whips out of the
blank plate of the octagon box, there's no ceiling in the laundry room
and won't be until *ALL* the wiring is done)

Also, in situations where someone's already been there and pulled
somewhat-newer Romex, do you generally consider it acceptable to
"repurpose" it if it runs where I need it? This is all the old NM not
NM-B, and for extra goodness some of it has a 16AWG ground. Is this a
big deal? Repulling it is not the end of the world, just a minor PITA.
I know it's not the best it could be, but ISTM that it should be
acceptable...

Oddly enough, this whole line of thought was prompted by the light at
the bottom of the stairs going out as I was pulling a piece of Romex
through the same space. Whenever I knocked against one of the pieces of
BX going into the ceiling box (I was reaching above the ceiling space
between the studs) the light would go out, and then when I touched it
again it would come back on. I figured this needed immediate attention,
and I just imagined that I'd find that I'd have to repull all of the
runs that entered the box due to it being fried. Imagine my surprise
when I pulled it down and everything looked fine inside, but when I
removed the lampholder itself the neutral screw was loose. OK,
reinstall, works. Left it dangling from the wires and carefully wiggled
the two wire nuts inside the box. When I wiggled the neutral, the light
would flicker. Not good! removed wire nut, here it didn't have any
spiral steel insert and was very loose on the wires. Some electrician -
presumably back in 1948! - didn't notice it, and here it was to freak me
out 60 years later... A new wire nut out of the electrical drawer and
all is working fine now

nate

(getting in practice for all the hidden work...)

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