#14 Romex To Light From #12/20-amp?

The way I was taught it, many years ago, if you have a 20A circuit then every item on the circuit needs to be able to handle 20A -- wires, outlets, switches, etc. Really, what is the difference in cost between #14 and #12 wire? Yeah, it is a bit stiffer and harder to work with but you aren't going to be doing it too often. I always remind myself that if a fire occurs and the insurance inspector shows up I don't want him finding anything stupid that would let the company wriggle out of paying up.

No, unless you change the breaker to 15 amps.

Yes, you're on the right track.

As I understand it, at least in Michigan, If you use a 20 amp circuit/breaker, code requires 12 gauge wire. 15 amp requires 14 gauge. Therefore, the 14 gauge would not be code if using on a 20 amp circuit.

That also should not be code compliant as someone could see the 12 guage wire coming off the breaker and change it back to 20amp.

Harry K

Maybe, and I see your point, but AFAIK, it's not a code violation, unless you have a cite that says otherwise. Anyone changing a breaker to a higher rating should only do so after checking everything on it and not just by making assumptions.

In the case in question, I don't see all the fuss. I'd just use

What code is that? The NEC does not address what an unqualified person might do later.

That attitude is exactly why we have one-size-fits-all requirements in the code. People are stupid. Maybe you don't care if the next owner of the house burns it down.

What "attitude"? And what "one size fits all" requirement in the NEC are you referring to? Please cite. AFAIK, it's perfectly code compliant to use either 12 gauge wire or 14 gauge wire on a 15 amp breaker. And IDK of any requriement that says if you want to use 12 gauge for a very long run to reduce voltage drop, then install some 15 amp receptacles on the end or some lights, using 14 gauge, that it's not allowed. If you have the section to cite, I'm sure we'd all like to see it.

And I'd say that people who are stupid and unqualifed should not be changing breakers in a panel. Because if you operate on that premise, then they could put a 50 amp breaker in and hook 12, 14, or 18 gauge wire to it.

And even if you weren't.

NEC code does not even address anything about WHO wires it. Ever hear about getting wiring inspected when selling a house? Violations don't pass no matter who screwed it up.

Harry K

Not exactly true.

The point wasn't what NEC says about who wires it. The point was that NEC doesn't prohibit what you and another poster claim. Give us a cite to where the NEC says that you can't install 12 gauge wire on a 15 amp breaker, then use 14 gauge to extend the run to some lights. AFAIK, there is no such restriction and Gfre apparently agrees.

I'm not in that list so I guess I should stop reading all the quotatoins from it and citations to it given here. That will save me some time.

Interesting implication was that someone who changes the breaker to 20A if the wire is #12 (without investigating) is unqualified.

So do I. The NEC is interested in minimum wire size.

You might increase the wire size for a long run to decrease voltage drop.

Maybe you should be calling someone who is on that list ;-)

Seriously, there are other books that interpret the arcane language of the code. In fact the first sentence of my cite is from the NEC, the rest is from the NEC handbook, one of those interpretations. That is what most mortals should be buying anyway. It gives you the code, then explains what they are saying.

As a matter of fact, at other places in the code you will find that under certain circumstances e.g. long runs from the breaker box, it REQUIRES that 12 gauge wire be used on 15 amp circuits...

The Handbook is almost required to understand the Code Book. Especially the drawings. I have not looked at a Code Book in a long time, but don't recall any drawings in it to explain the language.

That just says who it ( the code) is intended to be used by - and does not say anything about who does the work. ( as long as the installation is inspected by " inspection authorities exercising legal jurisdiction over electrical installations")

I always wondered why they don't make a residential version of the code. There is so much stuff in the NEC that doesn't pertain to residential. I think they could sell them to many people that find the NEC too confusing. (Isn't that everyone?)

I had a workbook when I was studying electricity (1978) that was only for house wiring. It showed pictures of a house and had sections that were broken up as parts of the home. It has stuff like service, kitchen, bath even CATV. A book like that could sell to a lot of home owners that DIY.

I just tried to Google for it and didn't find anything similar.