How to Add an Outlet to an Existing Light Switch

Pull the light switch you are interested in using out of the wall. In order for you to use the switch, it needs to have two sources of power connected to it. You will know it has two sources if there are two white wires, two black wires and two green wires attached to the switch. If there is only one source, the switch does not have live power and will be useless.

Determine where you want to install your outlet. Make sure there will be no studs in the way by using a stud finder. Mark the location on the wall with a pencil. Outline the back of your electrical box and cut out this hole with a drywall saw.

Drill a hole through either the bottom board or the top board of the wall framing with a 3/4-inch drill bit so you can enter the space the new electrical box will be positioned in. Put the electrical box into the hole.

Run 14-gauge, two-conductor wire from the switch to the outlet. If the hole you drilled is coming up through the bottom board of the wall framing, you will need to run your wire down through the basement and into the box. If the hole is in the top board, run the wire through the attic. Push the end of a steel fish tape through the holes in the reverse way the wire will be coming. Attach the ends of the wire to the fish tape and reel the tape back up. It will drag the wires with it, making running the wires much easier.

Remove the black wire from the screw on the side of the light switch. Cut a 4-inch piece of black 14-gauge, two-conductor wire. Strip both ends. Bend one end with a pliers and wrap it around the previous screw. Tighten the screw to hold the wire in place. Attach the other end of the short black wire to the black wire you had initially removed. Screw on a wire nut to hold these wires together.

Cut a piece of red 14-gauge, two-conductor wire long enough to stretch from the light switch to the outlet. Strip both ends of the wire. Bend one end and wrap it around a screw on the side of the switch. Tighten the screw. Feed the other end of the wire down to the outlet.

Remove the white wire and run it down to the outlet. Loosen a screw on the outlet and wrap the white wire around it. Tighten the screw. Loosen another screw on the outlet and wrap the red wire around it. Tighten the screw.

Attach the ground wire, it will be either green or bare, to the green grounding screw on the outlet. Tighten the screw on the top of your electrical box. This will cause the clamp on the back to tighten against the drywall and hold the box in place.

Push the light switch back into the electrical box and secure it with screws. Break off the tab in the middle of the outlet to allow the switch to power it. Push the outlet into its box and secure it with screws. Put the face plates on and secure them with screws.