How to Add Extra Switches at Different Locations for the Same Light
- 1). Turn off the power to the circuit powering the light and the switch by flipping off the breaker in the service panel.
- 2). Unscrew and remove the cover plate from the switch and unscrew the switch from the electrical box. Disconnect all the wires and discard or recycle the switch.
- 3). Cut a hole in the drywall at the location of the switch you want to add. Trace the back of a remodeling electrical box on the drywall and cut around this outline with a drywall saw.
- 4). Run a length of 12- or 14-gauge 4-strand cable, with an extra red wire, between the two switches. Use the same size cable as in the existing circuit. Pull the cable going to the light out of the first switch box and run it to the second. Pull the cables through the backs of both electrical boxes, giving yourself about 8 inches of slack, then install the remodeling box for the new switch in the hole by hooking the anchors around the back of the drywall and tightening the screws in front to secure the box to the wall.
- 5). Strip 6 inches of sheathing from the ends of all the cables with a utility knife, and expose 1/2 inch on the ends of the insulated wires with a wire stripper. Begin making connections at the original switch box.
- 6). Connect the black wires coming from the live circuit and going to the new switch to the two brass terminals. They are usually located on the top of the switch, or either side. Connect the red wire going to the new switch to the common terminal, which is colored differently than the other two and is located below one of the brass terminals. Twist the white wires together and screw on a wire cap. Twist the bare ground wires together, leaving one end longer than the others. Connect the long end to the green ground screw on the bottom of the switch.
- 7). Move over to the other switch and connect the black wires coming from the first switch and going to the light to the brass terminals. Connect the red wire to the common terminal. Twist and cap the white wires, then twist the ground wires together and connect them to the ground screw.
- 8). Push the wires into both electrical boxes and screw the switches onto the boxes. Screw on the cover plates, then turn on the power and test the switches.
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