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#61872 - 02/03/06 07:28 PM Wiring Timeline  
BigJohn  Offline
Joined: Mar 2004
Posts: 391
Boston, MA
Been running into a lot of old wiring lately and thinking it'd be interesting to know how old a lot of this stuff is.

Wondering if anyone knows the time periods for when a lot of this stuff was used:
  • Knob & Tube: 1890-1930?
  • Whatever that stuff is that was pulled through abandon gas-lamp piping: ?
  • BX w/ cambric insulated conductors/no EGC: X-1940?
  • NM w/ fabric sheath and cambric insulated conductors/no EGC: ?
  • NM w/ fabric sheath and plastic/thermoplastic insulated conductors/undersized EGC: ?
  • Aluminum NM: 1965-1975?

Just guessing on the dates. Anyone know any answers or have any other wiring types?


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#61873 - 02/03/06 07:36 PM Re: Wiring Timeline  
Tiger  Offline
Joined: May 2005
Posts: 706
Crystal Lake, IL USA
Interesting topic, BigJohn.

My only addition would be...the earliest use of varnished cambric with flexible metal wrap I've seen is close to 1900 at the Dole Mansion in Crystal Lake, IL. He used European craftsman and probably had access to materials not generally available. I'm working on another home in the same neighborhood (and approx.time period) which has varnished cambric in conduit.


#61874 - 02/03/06 09:16 PM Re: Wiring Timeline  
renosteinke  Offline
Cat Servant
Joined: Jan 2005
Posts: 5,316
Blue Collar Country
K&T was used in homes right up to the early '60's. when the acceptance of ground wires sounded the death knell to this method.

Romex first came out during the Depression, with paper around each insulated wire, and a cloth jacket over the whole.
In the '60's, it was allowed to have a ground wire that was smaller than the conductors. Romex from this era will have a #16 ground wire.

#61875 - 02/03/06 09:50 PM Re: Wiring Timeline  
Sixer  Offline
Joined: Aug 2005
Posts: 265
My home was built in 1939 and wired with knob & tube - minimal wiring I might add. One overhead light in each room on main floor, one light on top floor, one receptacle in kitchen (for iron), one in living room (for radio).....all fed from a 30 amp 4 circuit panel. Wow, have things changed since then!


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#61876 - 02/03/06 10:16 PM Re: Wiring Timeline  
jdevlin  Offline
Joined: Aug 2002
Posts: 402
welland ontario canada
The house I live in my father built in 1957/8. It has romex with ground wires(#16 I think). Also has breaker panel original to house with separate 100 amp fused disconnect.

House is in Ontario Canada.

#61877 - 02/03/06 10:51 PM Re: Wiring Timeline  
BigB  Offline
Joined: Mar 2004
Posts: 721
Tucson, AZ USA
Hey Dave, where is the Dole mansion? I left Crystal Lake when I was 13. I remember a Dole Avenue, where I used to mow lawns, just a block or 2 off Rt. 14 I think. Haven't been back there in almost 30 years.

#61878 - 02/03/06 11:02 PM Re: Wiring Timeline  
BigB  Offline
Joined: Mar 2004
Posts: 721
Tucson, AZ USA
Big John, there's a good book called "Old Electrical Wiring" by David Shapiro. It has a section of history and dating. Most of the K & T I have seen was from the 1800's till the early 30's, then it seems BX became the choice. Aluminum wire has been around since the 40's,but wasn't used widely till the 60's & 70's, mostly from 1965 to 1973, or the Vietnam years.

#61879 - 02/04/06 01:45 AM Re: Wiring Timeline  
gfretwell  Offline

Joined: Jul 2004
Posts: 9,142
The reduced size neutral wire was available in the early 50s. The house my parents built in 1955 had it. I understand this was necessary to pass "GI Bill" inspection but that may not have actually happened outside the DC area.

Greg Fretwell

#61880 - 02/04/06 06:44 AM Re: Wiring Timeline  
Tiger  Offline
Joined: May 2005
Posts: 706
Crystal Lake, IL USA
Check your email BigB. Sorry I called you John(confusion with BigJohn). Check out Lakeside Legacy, which states the Dole Mansion was built in 1865, not 1900. Is it possible flexible varnished cambric was around in 1865??? It's a three story with basement & didn't appear that the wiring was added after original construction.


#61881 - 02/04/06 09:58 AM Re: Wiring Timeline  
Active 1  Offline
Joined: Feb 2003
Posts: 687
Grayslake IL, USA
Dang, Daves working at the Dole Mansion. Last I knew it was a day care for children, somewhere to serve court ordered comunity service, and a half way house for drug addits. Not the best combination IMO.

What's varnished cambric look like?


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