Author Options:

How do I install a new electrical outlet? Answered

I need guidance on how to install a new electrical outlet to an existing wall.  My bathroom only has one electrical outlet, and it's located on the vanity light over the sinks (see photo close-up of light outlet on outdated fixture with rad vintage pastel ikat wallpaper). 

More info: 

Usually this should be pretty easy, since there should be an outlet on the other side of the wall that you can just tap in to; but there's no outlets on the other side of any of these walls (see wall descriptions below).  There are electrical wires running through these walls though, powering lighting and heating.  So, can I just cut a hole in the wall, reach my hand in, grab a random wire, cut it, splice in wiring to a new outlet, and magically everything works?  Probably not that simple.  I can grasp the basics involved in this, but I'm not 100% certain on how to proceed with my situation since I don't think I need to deal with feeding up new separating wiring from the basement but I also just can't easily tap into an adjacent existing outlet.   

Floor plan:

There's 2 switches at the bathroom entrance: one for the lights, one for the bathroom fan. The light switch controls 2 light fixtures: the one overhead light (it's a light/fan combo) as well as the lighting above the sink.  See scan image for rough sketch of current electrical floor plan.

Wall descriptions based on sketch:

Left wall: interior wall; on other side of the wall is an electric baseboard heater; door to hallway
Bottom wall: exterior wall; window
Right wall: interior wall; adjacent room is unfinished "attic" area above garage with sloped ceiling*
Top wall: interior wall; adjacent stairwell; wall-mounted light fixture with outlet; small under-cabinet baseboard heating vent thing

I would like to know if/how I can tap into the electricity of that sink light fixture to be able to relocate the electrical outlet lower, closer to the sink counter, and possibly off to the side (so, not central to the counter as it currently is).  See scan image for rough sketch of proposed electrical floor plan (ignore birds, I was using scrap paper).  I realize if I were to relocate it off to the side, I'd need to drill through studs and make more more holes in the wall, but that's fine, as I was thinking of creating storage space between the studs anyway.

I'm planning on replacing the current sink light fixture with either a) another wall fixture in the same location, b) 2 separate wall fixtures, one above each sink, or c) 3 separate wall sconces, a leftmost one, a center, and a rightmost one.  I haven't decided on what will look and function the best.  

I'm sure there was a much more succinct way of asking this question and describing my situation, but I am clueless about electricity and wiring and whatnot.  Despite my inexperience and ignorance I still feel like this is a task I'm capable of, but I'd like to seek the guidance of you wonderful Instructables' folks on how to do this.  I'd like to know where you think the outlet(s) should go based on the information I provided, and then how I get the power to that outlet without electrocuting myself and frying the house.  

* I first was going to say that this attic ceiling outlet is the nearest thing to an adjacent outlet, but I just remembered there's an outlet at the top of the stairs, adjacent to the attic (meaning, not on the other side of a bathroom wall).  The attic ceiling outlet is controlled by a light switch inside attic entrance anyway, and this is an insulated roof wall too. 


It's easy. You pick up the phone and call a certified electrician.

You don't want to mess with AC and you certainly don't want to skip on any laws or regulations regarding outlets in a bathroom. It's one thing to replace a outlet or switch. It's another when you have to run new cable and consider building codes and possibly have to have the work inspected by the city/county.

Thanks for your honest answer. I realize the calling a professional might seem like a lame answer, but I suppose it's the only right answer in this situation. Even if I was experienced in doing light electrical work, I'm not a trained and insured professional up to date on building codes and regulations and whatnot. Since this house is being prepped for eventual sale, then it'll be under more scrutiny too with regards to that I'd imagine.

If you do it yourself and don't do it right then you could cause a fire in the house or electrocute someone. If you do cause a fire and your insurance can confirm it was due to work that you did and wasn't up to code then you could loose your claim.

You could remove the vanity light and install a decorative electrical box, reinstall the vanity light on top of the box and run a matching conduit to where you want the electrical outlet. It is a practical solution if you do not mind decorative boxes and conduits on your wall. I have done the same on a kitchen to have an outlet where I wanted it.


5 years ago

This must be an old house. They used to think there was no need for outlets in bathrooms, after all they didn't even have electric shavers much less hair dryers. Is your wiring up to date? Does it use 3 wires or is it a fuse box with those ancient 2 wire cables?
This is probably not an easy job, depending on the layout. If you have a basement that is not finished then you can bring a wire up from underneath but drilling into the middle of a wall with out missing is pretty hard. The best way is to take out a section of the wall board, or Sheetrock, drill the holes for the wire (assuming you can use that instead of conduit), place the boxes, run the wire and finally close the wall up. I did something like this for a friend of mine when we tore out his old wiring and fuse box and replaced it all with new up to code stuff. To do the bathroom right we just striped the walls down to the studs and wired it all the way it needed to be.

In Montana you are allowed to do improvements like this on your own BUT they need to be inspected by the electrical inspector and pass. Often he (or she) will tell you something needs to be done differently and then come back after you have fixed it.
It all depends on the building codes where the house is.
Another thing Montana lets you do is have someone help you with the project. However unless they are a licensed electrician, plumber or HVAC they are not allowed to charge for their services. So your friends can help but you can't pay them for it. What I have done though is to swap time for time. I spend 20 hours working on your house and you spend 20 hours doing something for me that I need done. That way its all legal, oh and you don't usually have to pay taxes on the time either.

There is another way, you can run a channel on the wall with the wires in it but it doesn't look to great.

I think the most simple solution would be to find an extension cord whose length is the exact distance, between the outlet on the light fixture above the sink and the height where you want your electrical outlet to be.

The next most simple solution is to do the same thing as the extention cord, but with a conductors inside the wall; i.e. you wire an outlet in parallel with the outlet on that light fixture.

Note the outlet on that light fixture is probably in parallel with the light in the light fixture, meaning that outlet only turns on when the light is on, and both of these are controlled by the switch by the door.  

Having that outlet be on only when the light is on, is good for loads you want to use only when the light is on; e.g. a hair dryer.  I mean unless you like to dry your hair in the dark.

In contrast, a load like the battery charger for an electric razor, it probably wants to be on for several hours, and it would be inconvenient to have it only be on only at the same time the bathroom light is on.

Also note, this trick of tapping into an existing circuit does not increase the total amount of power you can draw from that circuit.  That limit is set by the existing circuit breaker, and also corresponds to the gauge (thickness) of the existing wires in the wall.

Final note:  I think the rule for new installations of outlets in a bathroom, or kitchen, or on the exterior of your house, require that outlet be the kind that has a ground-fault circuit interrupter.  (GFCI)
I think any room that has running water in it, requires that kind of outlet. That kind of outlet is easy to spot  because it is the one with the little buttons on it that say [test] and [reset].  (Erm... at least that's what the buttons say in English-speaking countries. )  Such an outlet is more expensive than the usual plain Jane electrical outlet, which of course does not have its own built in ground-fault breaker, but like I was saying, I think this special GFCI outlet is required for new installation in rooms that have running water in them.

BTW, this advice about the outlet with the GFCI, the only reason I know about that is because I have a friend who is an electrician, and we were discussing it once, although I think we were both really drunk at the time.  So um... yeah.  You should definitely consult the actual electrical code  relevant to your country or province, wherever it is rules like that get written down...