[pwd77]

I would like to add a light switch to an existing wall.
There is presently a single-gang box in place. I would like to cut it out and change it to a double. Removing the box should not be an issue, I know how it is attached (I did it).
I have acces
S to the top of the cavity, there is a hole through the top plate where existing line is going.
Question: Can I feed electric line down the wall cavity for the new switch?

It will essentially be loose, rather than tacked against the studs. With luck I can run it close to the existing one, but more likely it will be against the drywall, so I can feed it past insulation.

Unfortunately I overlooked this switch until I was done putting up the drywall. :(

[biggsie]

The way you do the job depends on how hard it will be to run your wire

You may need a stud finder to find a cavity for wire to run

If there is attic above this wall you can drill hole for wire

Fishing wire may be a two man job ( 1 feeds --1 pulls)

Since it is INSIDE WALL I don't think you have insulation in it

Measure and plan before you drill -- wall 6" -- center 3"

I would use small 1/8" drill bit that is 12" long

Drill a hole in ceiling close to wall , above the switch

Then take a straightened coat hanger and push it up

Through the hole you drilled -- reference point for larger hole

[labman]

Having read your question, I don't see any problem. You may want to drill a second hole if the first one is going to be tight for a second wire. If you bend over the ends of the wire before fishing it through, it will be less likely to snag on the insulation.

If you are wiring it as a switch loop, be sure and mark the ends of the white wire with black tape.

[pwd77]

Thank you for your help! The suggestions are good. I think I have a good handle on how to get the wire where it needs to go.

It sounds like having a wire "loose" in the wall cavity is not a violation of code... correct?

[peter030205]

It sounds like having a wire "loose" in the wall cavity is not a violation of code...correct?

You have to use internal clamps on the device box to secure the wire where it enters. No staples required.

[pwd77]

You have to use internal clamps on the device box to secure the wire where it enters. No staples required.

Excellent, thanks!