On Thu, 28 Jun 2007 18:34:19 +0100, "Dave Plowman (News)"
wrote:

In article .com,
wrote:
Well, much of the "fires" due to faulty wiring are because we have
*had* wiring as a general condition in most houses since the early
1900s, so after 100 years or so it gets a little tired, and when
overloaded can fail. Of course, 100 years ago, y'all had very nice
green lawns and gorgeous buildings.... but little electricity other
than the very wealthy.

You're not saying there is 100 year old wiring still in use?

My previous house, a Victorian built in 1892, had gas pipes leading to
all the lighting fixtures, capped off, and exposed knob-and-tube
wiring in the attic. Junctions were twisted and taped, hanging in
mid-air. I assume the original wiring was intended for lighting, and
over the years, as more loads were added, it became less suited. I had
a few joints open up, and eventually rewired it with Romex, with all
joints inside proper metal junction boxes. There's still a lot of
ancient fabric-insulated, twisted-junction knob-and-tube stuff around.

http://www.oldhouseweb.com/stories/Detailed/10327.shtml

http://www.knobandtubewiring.com/knob%20and%20tube.gif

It's common to see a fuse box, designed for 5 or 10-amp screw-in
fuses, to be full of 30's.


Around here, knob-and-tube was succeded by mandatory rigid steel
conduit and later, roughly 1960 maybe, Romex. Commercial buildings
must still use conduit, rigid metal pipe or the flexible MX stuff.
There is no requirement that old construction be upgraded, unless a
major remodel is done.


John