How to Install T8 Fluorescent Lighting

Written by philip schmidt
  • Share
  • Tweet
  • Share
  • Email

T8 fluorescent lighting is today’s energy-efficient version of the classic fluorescent “tube” lighting. T8 bulbs (or lamps, as the lighting industry calls them) are only 1 inch in diameter, compared to the 1 1/2-inch diameter of the old T12 lamps. The smaller diameter and improved engineering makes T8 lamps more efficient than T12. As for the fixtures, T8 fixtures install just like old T12 units. In a typical configuration, an overhead T8 fixture is controlled by a wall switch, with the fixture at the end of the circuit run.

Skill level:

Other People Are Reading

Things you need

  • Switch electrical box (as needed)
  • 14/2 NM electrical cable
  • Fluorescent light fixture (as needed)
  • Screwdriver
  • Hammer
  • Drywall saw
  • Cable clamp
  • Drill
  • Screws
  • Cable ripper or utility knife
  • Wire strippers

Show MoreHide


  1. 1

    Turn off the power to the source circuit at the home’s service panel (breaker box). Install a code-approved electrical box for a new wall switch, if you’re adding a new switch. If you’re connecting the fixture to an existing switch, remove the switch coverplate and unscrew the mounting screws securing the switch to the box.

  2. 2

    Run 14-gauge, two-wire, non-metallic electrical cable (labelled 14/2 NM; use only for standard 120-volt, 15-amp circuits) from the switch box to the fixture location. If necessary, also run cable from the power source connection (such as a nearby switch box or junction box) to the new switch box. Secure the cable runs as required by the local building code.

  3. 3

    Punch out one of the knockouts on the light fixture housing, using a screwdriver and a hammer. Cut a small hole in the ceiling to correspond with the knockout location (when the fixture is installed), using a drywall saw. Attach a cable clamp to the cable, and secure the clamp to the fixture housing with the provided nut.

  4. 4

    Mount the fluorescent fixture to the ceiling by screwing into the neighbouring ceiling joists or using hollow-wall anchors (such as toggle bolts).

  5. 5

    Prepare each cable end by removing the outer sheathing, using a cable ripper or utility knife, then strip 3/4 inch of insulation from the white and black wires, using wire strippers.

  6. 6

    Connect the fixture wires to the wires from the switch cable following the manufacturer’s wiring diagram. Install the cover on the fixture’s wiring compartment, then add the fixture lamps and lens, as applicable.

  7. 7

    Connect the switch to the power source cable, following the switch manufacturer’s wiring diagram. Mount the switch to its box and install the coverplate.

  8. 8

    Restore power to the source circuit and test the fixture and switch.

Tips and warnings

  • All electrical installations must conform to the local building code. Consult your city’s building department for recommendations and applicable code requirements.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.