Add an additional light switch at your existing light switch location.
You can use the power supply at a light switch to add a new light and switch, providing you do not exceed the current wattage draw of the breaker supplying electricity to the switch. Add up the current wattage on the electrical circuit you intend to use as the power source. Divide the wattage by 120 volts to obtain the amperage you currently draw on the circuit. If your total equals less than the current amperage size of the breaker, you can safely add an additional light fixture to the circuit.
Instructions
1. Turn off the breaker supplying electricity to the existing light switch inside the main breaker panel.
2. Remove the single-switch cover plate from the existing light switch, using a screwdriver. Turn the dial on a multimeter to 250 AC (alternating current). Touch a prong from the multimeter to a screw on the right side of the existing switch holding a black wire. Touch the other prong of the multimeter to any metal on the switch or electrical switch box. The needle on the multimeter should remain at zero if you turned the correct breaker off. Repeat this test for electricity on the remaining screw holding a black wire to the switch.
3. Remove the two screws holding the existing light switch to the electrical switch box. Pull the switch from the box and loosen the screws on the right side holding the black wires. Pull the two black wires from beneath the two screws on the right side of the existing switch.
4. Untwist the wire connectors holding the two white wires together and holding the two bare copper wires together and pull the two sets of wires apart.
5. Remove the electrical switch box from the existing light switch location. If the switch box is held on the wall with screws, remove the screws with a screwdriver and pull the box from the wall. If the box is held in the wall with nails, place a piece of wood inside the electrical box--taking care not to damage the electrical wires inside the box--and strike the wood with a hammer, loosening the box from the wall. Pull the existing light switch electrical switch box from the wall.
6. Place the template provided with the double-gang remodel switch box over the existing light switch location and trace around it. Carefully cut along the trace line of the double-gang box with a drywall saw to expand the size of the existing light switch location.
7. Place the template provided with the remodel ceiling junction box on the ceiling at the location you chose for your new light fixture. Trace around the template and carefully cut along the trace line of the ceiling junction box template with a drywall saw.
8. Pull a length of 12/2 nonmetallic (NM) electrical cable from your new light fixture location to the existing light switch location. Pull the electrical cable through a knockout at the back of the remodel ceiling junction box and slip the box into the hole you cut in the ceiling. Turn the three screws on the ceiling junction box clockwise to clamp the box into the ceiling.
9. Pull the original wires from the existing light switch location and the new length of 12/2 NM electrical cable through knockouts located in the back of the double-gang remodel switch box. Slip the box into the hole you expanded in the wall and turn the two screws on the double gang box to clamp the box to the wall.
10. Strip the exterior sheath from the new length of 12/2 NM electrical cable with a dual NM wire cutter/stripper at both the new ceiling light location and the existing light switch location. Remove 3/4 inch of insulation off the exposed black and white wires at the existing light switch location and the new ceiling light location.
11. Follow the manufacturer's directions to assemble your new light fixture Twist an orange wire connector onto the black wire from the light fixture and the black wire from the ceiling junction box, connecting them together. Repeat this connection for the white wire from the light and the white wire from the junction box.
12. Twist another orange wire connector onto the bare copper wire from the ceiling junction box in the green wire from the new light fixture to finish the electrical connection for the new light. Attach the new light fixture to the ceiling junction box with the mounting screws provided with your fixture.
13. Cut two pieces of 12-gauge solid black THHN electrical wire 6 inches long. Strip 3/4 inch of insulation off both ends of both wires, creating two black pigtail wires. At the existing light switch location, twist a red wire connector onto the two black pigtail wires and the black power supply wire to connect the three wires together. The power supply wire connects directly to the breaker that supplies electricity to the existing light switch.
14. Reinstall the existing light switch into the new double gang switch box. Twist a black pigtail wire around a screw on the right side of the existing switch and twist the black wire from the original light fixture to the remaining screw on the right side of the existing switch. Attach the existing light switch at the top and the bottom of the double gang switch box, using the screws you removed in Step 3.
15. Add the new switch to the new double-gang switch box. Twist the remaining black pigtail wire around one screw on the right side of the new switch and twist the black wire from the new light fixture around the remaining screw on the right side of the new switch. Attach the new light switch at the top and the bottom of the double-gang switch box, using the screws provided with the new switch.
16. Cover the new double-gang switch box, wiring and two light switches with a double-switch wall plate. Turn on the breaker supplying electricity to the existing light switch and the new light switch inside the main breaker panel.
Tags: light switch, existing light, existing light switch, light fixture, light switch location, switch location, wire from