Replacing an Existing Light Fixture
These steps are generally applicable to replacing existing household light fixtures. New fixtures should have instruction sheets included with them, so be sure to read those instructions! They may not be written in an easy-to-follow manner, but they may have specific information unique to that fixture. At the bottom of this page there is a printable PDF summarizing what’s described here in six steps.
Turn the power to the existing fixture off! It’s not enough to just turn it off at the switch. Turn off the breaker and confirm that the power is off by turning on the light switch and ensuring the light does not come on. You may need to bring a light in from another room on an extension cord to work.
- Remove the bulbs and shades from the existing fixture
There will be a screw or screws which mount the existing fixture to the junction box in the wall (or ceiling) behind it. Remove those screws. Be prepared to support the light fixture when it comes loose. It won’t come off because it’s still connected by the wires, and you don’t want to pull the wires out of the wall, the fixture, or have the fixture crash to the floor.
There will be 2 or 3 wires connected from the wall to the fixture. There will be solid copper wires from the wall, connected to smaller wires from the fixture with wiring nuts. These are colored plastic (yellow, orange, white, black, green, it doesn’t matter).
- The wires from the wall should be black, white, and un-coated copper if it’s present. If they aren’t, be sure to note which wires are connected to the black and white wires on the existing fixture. Treat whatever is connected to black as the black wire, and whatever is connected to the white wire as white.
- Unscrew the wire nuts from the wires. They simply unscrew from the ends of the wires by turning them counter-clockwise several times.
- The bare copper wire may be screwed to the fixture directly, so loosen that screw and detach that wire as well.
The existing fixture should now be free, put it to the side to later re-assemble and sell on Craigslist, donate to your favorite charity, or take to a reclaimed building materials business.
Attach any mounting hardware which came with the new fixture. Usually this will help hold the fixture while you connect the wiring later.
- Support the new fixture close enough to the junction box in the wall so that you can connect the wires from the wall to the wires from the new fixture.
Make sure the wires on the new fixture are stripped. If the wires are stranded (many little strands instead of a solid wire), then twist the strands together so they stay together and act as one wire.
Twist (now clockwise) the black wire from the fixture onto the stripped end of the white wire from the wall, making sure to get as much metal to metal contact as possible. Then screw the wire nut over the ends of the two wires. Turn the wire nut clockwise until it won’t turn anymore. If it won’t stop turning, then remove it, re-wrap the wires, and try again.
- Once the wire nut won’t turn anymore without twisting the wires, hold the wiring nut and try to pull each of the wires out of it. You should not be able to easily pull either wire out. If you can, then re-wrap the wires and try again. It’s important that both wires are secure in the wiring nut.
Also verify that no exposed wire extends beyond the edge of the wiring nut. You should see no bare wire, just the insulation on the wires.
- Repeat with the black wire from the wall and the white wire from the fixture.
- If your new fixture has a bare copper wire (it may stranded or braided), then connect that to the bare wire from the junction box using a wire nut as with the black and white wires. If your new fixture doesn’t have a bare wire, then it may have a ground screw. It will likely be green, but it will be screwed into some metal piece of the fixture. Wrap the bare wire from the wall around that screw and tighten it, ensuring it doesn’t pull free easily.
- Now the new fixture is wired. Mount it to the junction box in the wall using whatever mounting method the fixture uses. Some screw directly into the junction box, others come with a bracket which connects to the junction box, and then in turn the fixture mounts to the bracket.
Once the fixture is mounted, add one or more light bulbs to it.
- Turn the light switch off
Turn the breaker back on to restore power. If the breaker pops into the center position (between On and Off), then there is a short in the wiring. Turn it off, find and correct the problem.
Back inside, turn the light switch on. Your fixture should light right up!
- If it doesn’t, or if you hear any funny noises like humming or popping, turn the light switch off immediately. There is a wiring problem which needs to be corrected. Turn the breaker off, identify the issue and correct it.
Here’s a printable PDF summary of How To Replace an Existing Light Fixture.