Confused on how my bathroom GFCI is wired. See pictures

I need to bring some more power to a part of my house (built 2007) and my breaker box is full, so I thought I would just jump off an existing low loaded breaker to accomplish this.

After some breaker flipping I found a 20AMP circuit, labeled "hall bathroom". After some testing, I have determined that this outlet is the ONLY outlet on this circuit. In other words, when I flip this 20AMP circuit to "OFF", this is the only outlet I can find that has no power. I removed the outlet from the wall and the wiring on it is something I have never seen before (see picture and diagram). Since there were two jacketed wires connected to the outlet, I assumed that there had to be another outlet/light on the circuit. I went into the attic and located the wires and followed both of them to their source. Rather than clearing things up, it made them much more confusing.

The jacketed wire with 4 different wires in it (black, red, white, ground) I followed back to the breaker box. The jacketed wire with 3 different wires in it (black white ground) went to what looks like my front outside outlet and then to my backyard outlets and then finally back toward the breaker box. The crazy thing to me is, with the breaker to "OFF" these outlets still have power. See diagram below, can anyone shed some light on this?

 

Terminology:That ia 3-conductor cable not wire. (The grounds aren't counted.)It sounds like a multiwire circuit. You should have two breakers together, one with a black wire and one with a red wire. They are supposed to be handle tied (or a 2-pole breaker) but often they aren't. Do you have a red and black wire from the same cable going to two breakers?

 

Taping into your bathroom circuit for "other parts of the house" is a code violation. 210.11

 

But in earlier code cycles it was common to put outside receptacles on the bathroom circuits. Those would be grand fathered. However if this is a multi wire circuit it may not be a violation under even newer code.

 

You can bring up old Granddad if you want, but in this case, there are no other outlets serving other locations on that circuit now. If this was part of an inspected remodel in my neck of the woods, it would fail. Just saying. Good luck!

 

Thanks for the comments! I am unfamiliar with multiwire circuits and it sounds like that could explain this but wouldnt that mean that the 2-conductor cable should just terminate at the last outlet rather than go back to the breaker box?

In my diagram I show the cables going back to the breaker box but this is assumed. I followed the cables to about 5-10' away from the breaker box assuming thats where they went since thats the direction they were headed.

Later today after work I am going to try to follow those wires to directly above the breaker box and see if I can find which breakers they terminate in.

PS Thanks for the code information. I will definitely have to keep that in mind! I might have to reconsider jumping off of that bathroom circuit and either look at jumping a different circuit or maybe trying to replace some of my breakers for slimmer ones to make room for a brand new circuit which sounds like a bit of work.

 

That doesn't make sense first you say there are then you don't. And grandad isn't home if multiwire.

 

A multiwire circuit consists of two hots on opposite legs of the 240 and one neutral. If it is multi wire it is probably code.

 

His 20A bathroom circuit supplies that bathroom outlet. That circuit cannot have other outlets. Extending this circuit would be considered new work or remodeling in my opinion and should be held to the standard of current code. So an extension to another location other than that bathroom is not compliant.

In addition, there is no mention of a grandfather clause in the NEC. And the OP said the house was built in 2007 anyway.

Have a nice day.

 

Assuming this is a MWBC and one circuit feeds the bathroom receptacle, there is no reason why the other circuit could be extended. I do however think I see a code violation in the picture. It appears the MWBC splits in this box and the neutrals are terminated through the receptacle rather than being wirenutted and pigtailed for the receptacle. This house was built in 2007, the requirement to tie the handles of the breakers on a MWBC appeared in the 2008 NEC as I recall.

 

I was not referring to the assumption that this is a mwbc.

 

The NEC is not retroactively enforceable. The term "grandfather clause" is a legal term. If a person is only changing a GFCI and not modifying the wiring, they are not required to bring it up to current code definitions. Having been built in 2007 may red flag some of the wiring, but this box could also be used as a junction and have nothing to do with the GFCI. Texastravis, if you could pull the receptacle further out of the box so we can see the exact wiring, and post a pix, it may help a little.

 

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