How to Wire a Switch Leg For a Light

A lot of older homes have light fixtures that must be switched on by means of a pull chord or pull chain hanging from the light fixture itself. Because the light fixture is normally in the middle of the room it can be really inconvenient having to walk into the middle of a dark room to pull the chain to turn the light on.

Installing a switch leg for a light fixture is a medium DIY job that can be carried out by a homeowner with a few simple tools, a little knowledge and some caution.

Follow this procedure and you will install a switch leg with ease. Installation time should be 3 to 4 hours.


Mark the wall for the switch position.

Identify the fuse or circuit breaker for the light.

Set up an extension light if necessary.

Gather the required tools. You will need a hammer, screwdriver, keyhole saw and a snake.

Gather the required stock. You will need an old work box, a switch and cover plate, madison bars, a piece of 14/2 romex, some wire nuts, electrical tape and touch up plaster.


In residential construction the joists normally run from side to side in the home spaced on 16 inch centers.

The strapping will run from front to back in the house again spaced at 16 inch centers.

This ensures that you will have bays to snake your wires in.

Place a drop cloth on the floor covering the work area.

1. Remove the light fixture and if there is a box take out a knockout facing in the direction where the switch is to be placed.

2. Remember that if the switch is not in line with the light fixture you will have to make a hole or two in the ceiling to facilitate snaking because you cannot snake diagonally,

3. Run the snake from hole to hole in the ceiling drawing the 14.2 romex into the ceiling from the light to the wall just above the switch.

4. You will need to make a small cut in the ceiling and wall above the switch position so that the wire can bypass the wall header.

5. Snake the wire down the wall into the hole that you have pre cut for the old work box. If you are working with lathe and plaster it is a good idea to place your old work box so that you cut out one entire piece of lathe and a small piece of the laths at the top and bottom of the old work box. You can fix the box with Madison bars or sheet rock screws. After marking the box chip the plaster away to expose the lathe and cut the lathe neatly with the keyhole saw, holding the lathe in place so as not to make a large hole in unstable plaster.

6. Tighten the clamp in the old work box and remove the unused clamp and use the screw from it to attach the ground wire.

7. Put the white and black wires onto the switch screws, tighten and install and place cover plate on. It is better to use the screw terminals rather than the stab connections.

8. Identify the hot wire at the light fixture and open the wire nut joining it to the fixture.

9. Using wire nuts join the white wire from the romex to the hot wire at the fixture; join the black wire from the romex to the fixture wire.

10. Make sure that you connect the ground wire to the ground at the light fixture.

11. Re fix the fixture to the ceiling.

12. Make any holes in the plaster good with patch such as spackle or plaster of paris

13. Turn the power on and test the switch.