I have an new incoming circuit at box in garage that is not GFCI protected but I want to add a GFCI at that point (garage) and then add 2 more GFCI protected duplex outlets in garage downstream off the GFCI load yet still carry the original non GFCI circuit forward in same conduit run. Is this possible by splicing properly?

I was hoping to utilize the same conduit to add a couple non GFCI duplex outlets to bedroom above garage. My thought is that I will need to add additional conductors in conduit along with the downstream feed wires from first GFCI.

Will I just spice in first JB and carry the original non GFCI conductors (black and white) or can I share the hot for both? I don't want to add any unnecessary wires or conduits in the garage if not needed.

  • Good question. My follow-up for an expert is whether neutral can be shared.
    – isherwood
    Commented Oct 8, 2020 at 15:54

2 Answers 2


I do that all the time. For instance in our breakroom, I have black + white carrying non-protected supply, whilst purple + gray carry GFCI-protected supply. They all share the ground of the metal conduit pipe. Purple + gray land on the GFCI-protected outlets, and black + white land on the non-protected outlets.

You can pick ANY colors you want, as long as neutrals are white or gray, and hots are not (and also not green).

There is no way to "double up" and have white+gray (or purple+black) be the same wire. That would instantly trip the GFCI device. Anyway, THHN wire is cheap, so don't worry about it lol.

If you don't actually want to buy purple + gray wire (would have to go to an electrical supply), then just go ahead and either mark the wires with tape, or group them with tape so their relationship is clear. I'm a huge fan of colored tape for that, but it can fall off down the road.

  • I can fall off down the road, but it's less likely to if you stick with quality tape. One of those places where it really does not cost much to get the best stuff, and saves headaches later.
    – Ecnerwal
    Commented Oct 8, 2020 at 16:50

You can do that. Basically:

  • All grounds together
  • Pigtail hot & neutral coming in to the GFCI's box. From the pigtail, each gets a wire going to the GFCI "Line" side and a wire going on to the non-GFCI protected receptacle.
  • Garage downstream receptacles connect to the GFCI "Load" side.

There is no problem sharing the neutral. The key is that hot & neutral need to be together - you can't, for example, have hot on Line/Load but have neutral pigtailed to then bypass the GFCI (i.e., Line + direct to the other receptacles instead of coming off of Load).

The one catch though is that the bedroom receptacles very likely have a code requirement (but varies by area - provide state/county/city and we may find an answer to that) to have AFCI. That is a little different from GFCI, but similar in that it is a special device that has to go somewhere. Unlike GFCI, which is just as effective at point-of-use (first protected receptacle) as in the main panel, AFCI is most effective when it can protect the bulk of the wire, so it is best as part of the circuit breaker or near the circuit breaker.

  • An AFCI breaker would protect the entire circuit, adding additional protection to the garage GFCI circuit. Would that cause any problems for the GFCI outlet in the garage?
    – FreeMan
    Commented Oct 8, 2020 at 16:07
  • 1
    I was wondering that myself. This likely would be a situation where both would be required - GFCI for garage, AFCI for bedroom. Logically they shouldn't be incompatible - though this may be a case where sticking with a family of products (Leviton or whatever) might minimize any false-positive style interactions between the devices. Commented Oct 8, 2020 at 16:15
  • first box has the incoming black hot white neutral and ground. I want to put a gfci receptacle here. Conduit exiting this JB to next JB . How many wires are exiting this first JB in conduit if next JB will have a GFCI but also continue the "non" gfci circuit in same conduit so I can have the ability to branch off with non gfci . in future.?
    – journey
    Commented Oct 9, 2020 at 12:09
  • @journey You will have 5 wires going out - hot & neutral pigtailed to "line" side of GFCI (these pass through the box to the next **non-**GFCI location) hot & neutral from "load" side of GFCI (these daisy chain to the next GFCI-protected location) and ground (one ground for everything). Commented Oct 9, 2020 at 14:39
  • Thank You. I am using a 4" square 2 1/8" deep box at first location. If I have this correctly it will have a 3 wire splice (incoming hot and neutral plus the tail going to line side of gfci at this box, plus the non gfci . it will hopefully be big enough for three 1/2" thinwall connnectors plus plastic bushing plus the 3 wirenuts and was hoping to make this a double duplex box but I might be pushing the box fill capacity. I wanted to branch in both directions (left and right) off the gfci but dont think its possible
    – journey
    Commented Oct 9, 2020 at 21:36

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