Installing a new light fixture is a great way to transform a drab room
into a dazzling one. However, correct wiring and solid installation are
critical. This page shows how to hang a fixture safely and securely.
Learn the temperature rating of your existing wires and verify your
new light will be compatible. Many lights, especially ceiling-hugging
fixtures, require connection to standard 90-degree C-rated wire.
Wires installed before 1985 often don’t have insulation that can
withstand this higher temperature.
Heavy fixtures require strong electrical boxes. Inspect your existing
electrical box and make certain it’s firmly mounted to solid framing,
especially for heavier fixtures. If the new fixture is particularly
heavy -- more than 25 lbs. (12 kg), consider replacing the old box
with a ceiling-fan-rated box.
Key Installation Steps
Avoid trouble by assembling and adjusting the mounting parts before
you climb up the ladder. Also, if the new fixture has silver or
gold lamp-cord wire, identify the neutral side by feeling for
ridges, indentations or square edges; the hot wire will be smooth.
1. Turn off power and test all wires with a voltage detector to
make sure the power is off. Disconnect the light fixture wires and remove the old fixture. Inspect and test the box for secure
2. Install fixture strap and threaded nipple. Lift fixture into
position and thread fixture wires through threaded nipple. Attach
fixture firmly to ceiling box.
3. Connect the wires after you identify the neutral fixture wire and hot fixture wire. Attach the ground wire around the ground
screw and test the fixture before installing canopy.
A screw and cap nut assembly holds the fixture to
the fixture strap with screws mounted to a two- piece offset fixture
strap. Before installation, thread the screws through the offset fixture
strap and test-fit the canopy over the screws. The screws should protrude
only enough that the cap nuts will hold the fixture firmly against
A threaded nipple assembly mounts
to the center of a single flat fixture strap. This threaded nipple holds
the fixture to the fixture strap and acts as a conduit for the fixture
wires into the box.