How To Install A Light Switch In An Existing Wall

Unscrew the wire nut holding the two white wires together.

How to install a light switch in an existing wall.

Pull the switch out turn it on and test the terminals with a voltage tester. From the switch new 2 wire cable is run to the new light location. Adding an electrical box to your existing wall for a switch or outlet is easy when you have the right materials and know a few tricks. And you don t have to remove any drywall except for the box s cutout itself.

Wiring a new switch and light from an outlet in this diagram power is taken from an existing wall outlet for a new switch and light fixture. When you need to add an outlet or switch in an existing wall you need to use a special electrical box called an old work box an old work electrical box may be metal or plastic and is specially designed to be installed in an existing wall where it has no support other than the wall itself. Unscrew the wire nut holding the two black wires together on your existing light. Twist the wire nut onto the three wires to secure them.

Pull the switch from the box and loosen the terminal screws slipping the circuit. See the video above for more specific instructions. Remove the cover plate from the existing light switch. Turn the power back on and use a noncontact voltage tester to locate the hot wire.

The switch comes first in the new part of the circuit and new 2 wire cable is run to it from the outlet. Remove the two 6 32 screws securing the switch in the box. Unscrew the switch cover with a screwdriver remove it and unscrew the switch from the electrical box in the wall. Shop all lighting now.

If the wall is heavily insulated push conduit through the insulation and then feed wires or cable through the conduit.