Old wire thicker than new wire?

Jan 26, 2006 Last reply: 1 year ago 65 Replies

I use them when appropriate, but I've seen them fail (as you probably have). There are boxes which you cannot change unless you want to rip it out and replace with a bigger one. If the box is too small and the existing wire is crowded, wire nuts make me nervous. I'll use crimps, as long as there's enough wire to work with in case the crimp has to be cut off at a later date. For new work, I always install an oversized box so there's enough room to use wire nuts correctly.

That leaves Michael Jackson out of the picture :)

It's not a bitch to work with the soild #12 wire either after doing it for years and years....

Always pre-start the bends before cramming the wores in the box. Just cramming makes the job tough and is more likely to develop a short or broken wire.

Want a challenge, try using #10 wire in a standard box with an outlet or switch. When I used to work for electricians, I once ran into a house that someone had used a whole bunch of #10 for 15 and 20A circuits. It was definately a low loss, and would never overheat, but working with it was a nightmare.

Yes, please..... Stranded has been used in conduit for years. Unless this changed recently, this is not correct....

I'm still waiting for some measurements. It's amazing how these threads get lost in other discussions....

I always think the newer wire is thinner too, but legally is should be the same.

replying to Nexus7, d57tbird wrote: Old 14 gauge strips with a 12 gauge notch on my wire stripper. the newest batch of 14 gauge is too thin to strip well with my stripper. Visually, the old 12 gauge is like modern 10, old 14 is like modern 12. As the price of copper goes up, the wire gets thinner. It seems like it may be a more brittle or stiffer alloy in the modern wire. Not sure if the alloy allows more current or if we are being cheated.

The insulation on old type TW wire was thicker than THHN but the wire is the same.

The wire itself is the same size. The insulation is significantly thinner. The wire HAS to be the same size unless it is counterfit Chinese crap.

Never lived in Chicago then, haha. It’s all stranded and in conduit throughout the entire house

Is it still that way? I'd have thought they would have changed, at least for new construction.

Perhaps, or far more likely:

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I imagine that was justification for the original rule but a hundred years later, romex has not been the big problem

I imagine that was justification for the original rule but a hundred years later, romex has not been the big problem

Romex has a number of issues, particuarly when installed by amateurs.

In a very dense city like Chicago (or Manhatten), it makes sense to have strict fire safety requirements for electrical work, given the potential for disaster.

It'sa lot easier to screw up with stranded thhn than with romex

I found this and it makes some sense in the city.

Why is Romex illegal in Chicago? The change was pushed by the county's Building Department. Staffers there said house wiring known by the brand name Romex can be dangerous if the insulation is gnawed by rodents or punctured by nails.

A 17 year old thread with a few 5 year old posts, then this one.

A couple posts said #12 wire is smaller now.

And "Stranded is not code [NEC]"

(Both debunked)

This is probably a reply with the usual homemoanerhub quality and doesn't add anything. haha

Yes, but. What's special about Chicago compared to other cities?

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