Running wire in a finished wall

I am trying to install a sconce light fixture to a finished dry wall. I can't find in any books on how to run a wire from an existing outlet. I have an outlet just below where i want to attach the sconce. Do I tap the below outlet and then cut a round hole and attach the pancake box for the sconce? What kind of wire do i need and how do I know whether I am overloading the circuit? I am sort of novice in electric work but I am eager to learn ( without burning the house down )

Any suggestions are greatly appreciated.

 

Cut a hole for an old-work box where you want the sconce (not where the stud is, but within the same stud cavity as the receptacle). Hang something (a cord, thin chain, etc.) through the hole. Use a coathanger through a hole in the receptacle box to catch the thing you hung. Pull it into the box. Use that to pull a cable into the box.

60-watts on a sconce is unlikely to overload a circuit.

The wire you need will be determined by the size of the breaker. For a 15-amp breaker, you'll need 14/2 NM-B. For a 20-amp breaker, you'll need 12/2 NM-B.

Most good books on home wiring cover stuff like this. Which books have you unsuccessfully looked at?

 

Thanks for the info. I looked at the Homedepot "wiring" and "guide to home repairs. These books are pretty general. Your info is very helpful. I have other questions though. How do the wires typically run . The house is 20 years old if this helps. In other words, do wires within the wall run down to the source. Ideally I would like to run the wire from the sconce to the light switch located on the adjacent wall. Would this mean I would have to make several holes and drill through every 2X4 of the dry wall to feed the wire? Also, is it true that when I open the receptacle to add new wire, the gauge of the wire must be the same as the existing wire? Thanks again

 

Unfortunately, there is no "typical" that you can count on. If you see two receptacles on the same circuit on the same wall, you can make a pretty good guess that the cable runs through the studs between them (probably just above the level of the receptacles). But you can't be sure that it doesn't run up into the ceiling, across, and down.

In your situation, running a cable across the room is pretty easy if you have attic access above, or basement or crawl space access below. If you don't, then some drywall damage/repair is almost inevitable.

But you may not need to run the cable all the way to the light switch. Another option is to run the cable to the nearest thing that the light switch controls (ceiling light or wall receptacle).

It's a good idea to match the gauge of the wire to the gauge of the wire that's already there. It may or may not be required, but matching the gauge is a simple and effective algorithm, and it doesn't require you to figure out whether you are allowed to change the gauge or not.

 

Thanks a lot for the info. Just curious, how much this wire running can cost if i hire an electrician? Also, just from your experience, I have walted ceilings of about 15 feet high. How big of a pain in the rear it is to install recessed lighting up there given that there is no light fixtures currently installed? Also, how does one determine whether the recepticle is at the end of the run or not?
Again, thanks for your feedback. I am printing out all the replies!

 

Receptacles at the end of the run have just one cable into the box. Other receptacles have more than one. Not sure why you're asking, but it usually doesn't make any difference whether or not a receptacle is at the end of the run, unless it is a switched receptacle.

Cost vary widely from area to area.

Difficulty depends on the skill of the person doing it, and on factors that it is not possible to judge without seeing it. But what you want is certainly not impossible.