Replacing a Light Fixture

Electrical wiring in a home is somewhat akin to having extension cords and drop lights built into the walls. But, no matter how simple it might be there is a fear of electric shock that keeps many people from being comfortable with electrical projects.

Our favorite part of construction is electrical work. Electrical wiring in a home is somewhat akin to having extension cords and drop lights built into the walls. But, no matter how simple it might be there is a fear of electric shock that keeps many people from being comfortable with electrical projects. Actually, the most dangerous job in home construction is roofing and one of the safest is electrical.

One of the safest and easiest light fixtures to install is the type that mounts directly to the ceiling box with two screws. However, not every light fixture will adapt directly to the ceiling box. In such a case a mounting adapter bar is provided (or is available as a separate purchase) to allow the fixture to be mounted to the ceiling box. This is the one that we will show you how to install.

When purchasing a fixture, be sure to determine its maximum wattage rating and the maximum size bulb allowed. Never exceed the bulb size rated for a given fixture. This also goes for the fixtures you already have. Nothing can create a fire hazard more readily than a light fixture with oversize light bulbs. Grounding also is important. The bare wire in the ceiling box is the ground wire. The ground wire in the light box should be connected to the fixture mounting bracket at the location provided on the bracket. If there is not a ground wire visible in the fixture box, you might want to consult an electrician to determine how your electrical service can be upgraded to include a grounding system.

CAUTION: Before undertaking an electrical project, turn off the power at the main panel. Turning off the power to the light circuit being modified might not be safe enough. Often more than one circuit is in a single electric box. Also, make sure to purchase only UL-approved electrical fixtures.

Replacing most light fixtures is a simple five-step process:

Step 1: Removal of the old fixture. This is where it becomes important for the power to be turned off at the fuse box or circuit breaker panel. First, remove the shade(s) and the bulb(s). Even if the mounting screws can be accessed with the bulb and/or shade in place, their removal is important because a slip of the screwdriver could break glass and result in an eye injury. Remember: you are working above your head. With many fixtures, slightly loosening the mounting screws and then twisting the fixture is all that is needed to separate the base of the fixture from the ceiling. However, in some instances the screws will have to be removed. An electric screwdriver is invaluable. With the base dismounted from the ceiling, disconnect the fixture wires from the wires in the ceiling box. Do not save the wire nuts for reuse. There is the possibility that they were damaged when installed and could be further damaged beyond use during removal. If the wires in the ceiling box are not color coded, mark the one that is connected to the black lead before disconnecting the wires. A piece of masking tape will work, but just about any marking method will do.

Step 2: Install the mounting bracket. It usually comes with four screws, two long, and two short. Use the short ones to mount the bracket to the ceiling box. The screws that hold the bracket to the ceiling box attach to the box through the long, narrow slots in the mounting bracket. The slots are used to align the center of the mounting bracket with the center of the ceiling box. With the bracket centered and firmly mounted in place, attach the ground wire from the ceiling box to the appropriate location on the bracket. Finally, install the two longer screws in place in the threaded holes provided in the mounting bracket. Only two or three threads of the long screws should be inserted into the bracket. Most of the screw should be exposed to the room.

Step 3: Connect the wires from the new fixture to the wires in the ceiling box. It is important to connect like-colored wires when attaching the ceiling box wires to the light fixture ones. This is where it becomes important to know which wire was connected to black if the wires in the ceiling box are not color coded. Refer to step one for marking wires that are not color coded. And don't forget to use the wire nuts provided with the fixture to make the connection.

Step 4: Mount the fixture. This is the easiest part of the job. Place the keyholes in the base of the fixture over the two screws that were previously threaded into the mounting bracket. Once the heads protrude through the fixture base, twist the fixture so that the screws are positioned in the narrow portion of the keyslots. At this point the fixture can be released and the screws tightened securely.

Step 5: Install bulb and cover. Be sure to use the proper size bulbs. Bulb size should be clearly marked on the fixture. If not, purchase a different brand. Be sure to clean hand oil off the surface of each bulb with a soft dry cloth once it is mounted in place. Hand oils could cause a bulb to burn out prematurely. Finally, install the shade.

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