How do I add a "always on" GCFI outlet to this bathroom setup

Question

In the past I ran into an issue where I tried to replace the wall switch with a GFCI+Switch combo and found that every time I plug a device in, my vanity light comes on. Vanity light above sink is the only light source in this small bathroom and has a small shaving outlet embedded in the light base.

What's the right way to do this? I do have the ability to remove the in-wall medicine cabinet and run a new cable for a new outlet on that same wall. But I don't have good in-wall access to the current light switch.

Answer 1

Don't make it harder than it is!

I say as I write a long and complex answer lol.

Your concern is the vanity has a convenience plug which is not GFCI protected.

However, here's a secret about GFCI protection: It is a zone of protection not a receptacle.

You're accustomed to seeing a particular implementation of GFCI that contains a combo GFCI protection device + 2 sockets. Well of course it puts its own sockets in its protected zone, but it can protect anything else also. That's what the "LOAD" terminals are for. It is the only legitimate use of LOAD. Don't use it accidentally.

However -- you can absolutely use the downline protection feature deliberately.

The electricity going to this vanity must come from somewhere. Since you've already worked on it, you know which circuit breaker it is. So turn off that breaker and survey the house for what other points-of-use have gone dead.

Now guess at the serial route from point to point, and try to figure out one that is between the vanity and the electrical service panel (source). Strongly prefer a receptacle over a switch (still possible with a switch if power comes to the switch and not the light). Then open that up, photograph how the wiring is now, and then disconnect the downline hot wire... insulate it with electrical tape in case it's actually the supply hot wire (we don't actually care at this point)... then power the circuit back up to see if that cut power to the vanity. If it did, this is a good point to install GFCI *protection).

If it's a receptacle, it's a routine installation of a GFCI receptacle. Hook up the suspected supply hot+neutral only to the LINE terminals only, plug a lamp into the socket, go back and turn the breaker back on, and see if the lamp powers up. If it does, you have the right wires on LINE. Power back down, hook the others to LOAD and the vanity should now be GFCI protected. Trip the GFCI with the "Test" button and confirm the vanity loses power.

If you "accidentally" protect a large part of the circuit, shucks o-golly LOL. Make sure to label all receptacle outlets "GFCI Protected" and "No Equipment Ground" if applicable. If you hate the blue stickers feel free to use any marking method that is not hand-written. I like white cover plates + a P-touch or Brother label maker. Or if you know a bro with a laser etcher, go for it.

If it's a switch, that's a bit trickier, but still possible if the supply wires come to the switch first, i.e. there would be 3 hots and 3 neutrals inside the switch box, with all 3 neutrals spliced to each other. Because they make GFCI+switch combo devices too. Ask if you have that situation.

If the vanity is the very first point on the circuit, we'll have to resort to a GFCI circuit breaker (yeah, those too).

Answer 2

The only way I can see not running new wire would be to use a smart switch and a smart bulb. 2 Wires to the switch become Hot and Neutral, no load is connected.Bulb is wired always on as well. Wifi/Cloud/ZWave/Zigbee connects the signal from switch to bulb.

Traditional answer requires a new wire to the switch/outlet. Do you have access to the wall from above (attic) or below (crawl)? So you could drill a hole and use a fish stick to get to the switch box and pull in a new wire? Next would be to cut a strip of drywall out to run wire across the wall from where ever, possibly consider any outlets/wires you can access on the other side of the wall. The other would be if you cut into the wall and then could access wire/outlet directly above or below on another floor.

Answer 3

If you want to add a receptacle in place of the switch, you can rewire the switch feed at the vanity junction, and use the existing wire to bring neutral and line to the outlet, which you will use to feed a GFCI receptacle replacing the switch. You cannot use the switch wires for a receptacle without making changes at the vanity outlet box.

If this is your preferred set-up, then you will need a separate switch for the vanity: some vanity lights come with a built-in switch, or you can wire a surface mount switch from the vanity junction.

If your intent is to upgrade the safety in your bathroom and make the vanity receptacle ground fault safe, you have further options:

Find out where the feed ("2 wire cable") for the bathroom comes from. If it arrives via another receptacle elsewhere in the house, you could replace that receptacle with a GFCI receptacle and feed the bathroom from the "secondary" or "protected" side of that GFCI receptacle.

Alternatively you could install a new receptacle fed from the vanity outlet/junction box. If you have no access to the walls, you can run a surface mount conduit from the fixture to a surface mount outlet box, and install a GFCI receptacle in it.

You can also get an extension cord or "power strip" with built-in GFCI, plug it in the vanity light receptacle and securely mount it to or in the cabinet.