I'm doing some remodeling on a river cabin. It was built 50 years ago and most of it is not to code.

It's not mine and I'm trying to get my family to look at upgrading all the wiring. It doesn't even have outlets with grounds in them.

Also, for those who might be concerned, I do have some experience wiring. My uncle wired his whole home and came down to wire my dad's shop. He taught me and an inspector said it was wired better than some homes he'd been in. I know how to safely wire this project in, just not issue like this. If I can't find a satisfactory answer or I don't feel confident, I will call in a professional.

My issue is that I'm working on redoing a wall in the bathroom. There is currently a light fixture with a built in plug for plugging in something like a hair dryer. I'm replacing that light fixture and would like to add a gfci outlet in the wall before I add the FRP board I'm covering it with. The current gang box for the light is free floating and I'm going to replace it with a plastic one with the little wings that hold it in place. Being able to push it back I can read that the wire says 14/2.

Ideally all the wire would be 12/2, but I don't know when or if that will happen. I'll never use 14/2, so instead of buying a roll of that, can I use a piece of the 12/2 romex that I already have, and wire off the light to the outlet?

I understand that the outlet would only work when the light was on. I just want to make sure I'm not going to burn the cabin down. In my mind, it would be fine, because it's already wired correctly for 14/2, with the correct amp breaker, so if it hits a load too high for the 14/2, then the breaker shuts off. It just has the capability to run more power. I wouldn't be able to do the reverse, but this seems okay.

Am I correct on this or is there an issue I don't know about? Thanks. I did see similar questions, but none that I thought were exactly this issue.

  • "I'll never use 14/2" - really? Why not? If you separate lighting and outlets, 15 amp circuits are massive overkill for modern LED light loads, but 14 gauge is as small as you can go for wiring in the walls. So it has a lot of valid applications even if you are upgrading all the outlet circuits to 20A. But if you use (as I think you should) a dedicated circuit for a refrigerator or freezer, 15 A is plenty and then some for most modern units...so there's another application for 14 gauge.
    – Ecnerwal
    Apr 13, 2020 at 16:22
  • @Ecnerwal I'll never personally use it, because I don't plan to do a lot of wiring. I just happen to have some 12/2 from another project. I don't really want another coil of that laying around taking up space either.
    – Dalton
    Apr 13, 2020 at 16:35

3 Answers 3


Since you are redecorating you are allowed to use the 15 amp circuit that code allowed when built. however since you are changing the receptacle style a GFCI will be required. You are not required to replace the wiring in walls for this type of update. Just to clarify Modern builds are required to have a 20 amp circuit for the bathroom. you can have a duplex 15 amp as code doesn’t specify the size of the receptacle in 210.52.D . With older homes that were not required to have 20 amp circuits a 15 amp GFCI receptacle would be needed 210.11.C.3 requires a 20 amp circuit but again doesn’t state the receptacle size and a duplex 15 amp is allowed on a 20 amp circuit per table 210.21.B.2

You can start updating the wire size going larger is better and a 2 wire GFCI is safer than the old receptacle on the light fixture. I have updated quite a few older bathrooms that were inspected with this exact same change and they passed inspection. I would verify with your local jurisdiction uses 210.12 where the receptacle is not extended more than 6’

  • Thanks for the help. I'll look into all of this. If it starts looking too complicated for me, I'll put in the gang box and put a plate over it till they get ready to wire it correctly. I do plan to use a GFCI.
    – Dalton
    Apr 13, 2020 at 16:41
  • I think you are doing fine your plan to use 12 awg is good and will help in the long run to bring the cabin up to modern code.
    – Ed Beal
    Apr 13, 2020 at 17:34

I would say you are ok for now. Would be different if the current wiring was 12/2 with 20amp breakers and you were splicing in a piece of 14/2. But there is probably a section in the code book somewhere that states this is not acceptable practice.

  • The minimum wire size anywhere on a 20 amp circuit or a circuit protected with ocpd of 20 Amp is 12 awg.
    – Ed Beal
    Apr 13, 2020 at 17:32

You can run 12 gauge wire tying in to 14 Gauge. You can always go to larger gauge - but not here. The issue is amperage and grounding.
With the 14/2,the light is going to be 15 amp, or at least should be. You're required by code to have 20 amp outlets in bathrooms and they need to be GFCI protected. This is required for good reasons. Hair dryers, for example, all have high loads.
Then, the grounds, you don't mention them but this outlet once it's wired as 20 amp should be grounded with 12 gauge if grounding is available. Either way you need a GFCI.
What you should do is run a separate 20 amp circuit with 12 gauge and a GFCI either at the outlet or breaker for the bathroom. You can run other bathroom outlets from it where needed.

  • Why would you say a 14 ga circuit needs a 12 ga ground? Yes, current code requires a 20 amp circuit that serves ONLY bathroom outlets. Also, let's be real, GFCI outlets do a great job even without a ground wire. Apr 13, 2020 at 16:09
  • @honeydo Nothing in the cabin is grounded. Not my choice and it's something I'm pushing for, but it isn't there. I did plan on using a GFCI. If it's an issue, I'll install the gang box and put a plate over it till they get an electrician to rewire the whole place.
    – Dalton
    Apr 13, 2020 at 16:39
  • Not my down vote but with modern code in a bath room the entire bath can be on 1 circuit , or the receptacle feed the bathroom(s) receptacle outlet(s) such circuits shall have no other outlets 210.11.C.3. So other outlets where needed? Only in a bathroom.
    – Ed Beal
    Apr 13, 2020 at 17:27
  • Yeah! Definitely put in a GFCI! But the at some point the entire system needs to be properly grounded.
    – HoneyDo
    Apr 13, 2020 at 17:28
  • All I was saying is that the bathroom outlet needs to be 20 amp and if the circuit is grounded it requires a 12 gauge ground. I'll edit to be clearer.
    – HoneyDo
    Apr 13, 2020 at 17:33

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