Can someone tell me aprox. when knob & Tube wiring was stop being used? Just Curious.
It's trill being USED today... Installed as extentions, and repaired in kind TODAY...I've seen house built in the late 30's using BX. So it could have been a slow change over.
I'd love to see a copy of this if you know where to find it?According to an article I have by David Dini P.E. from UL Knob and Tube began to be phased out in the thirties and was no longer used for new installations by mid seventies.
memories
question missed on my 1st journeyman's test "SOLID knobs are permitted only for #___ and larger conductors"
View attachment 4585
I'd love to see a copy of this if you know where to find it?
I'd love to see a copy of this if you know where to find it?
Knob& Tube was the only permitted single family wiring method in the county where I served my apprenticeship in the 60s.
, this is the general transition of wiring methods I've observed in dwelling units built over the last 100 years.
K&T > BX (no bond wire) with rubber insulated conductors > clothed covered 2-wire romex with rubber insulated conductors > cloth covered 2-wire romex with thermoplastic insulated conductors (type TW) > cloth romex with reduced ground wire > plastic romex with reduced ground > plastic romex with full sized ground (NM) and TW conductors > modern NM-B and THHN conductors
Warning - boring post ahead.
In my travels doing residential work, this is the general transition of wiring methods I've observed in dwelling units built over the last 100 years. If someone could add some dates for these transitions that would be nice.
K&T > BX (no bond wire) with rubber insulated conductors > clothed covered 2-wire romex with rubber insulated conductors > cloth covered 2-wire romex with thermoplastic insulated conductors (type TW) > cloth romex with reduced ground wire > plastic romex with reduced ground > plastic romex with full sized ground (NM) and TW conductors > modern NM-B and THHN conductors