I am putting 2' X4' flourescent troffer lights in an Armstrong Prelude ceiling grid in my basement. Armstrong says don't put any weight on the grid, other places I have read place them in the grid and add extra wires to the grid around the lights. Code probably also requires that the lights be suspended from the joists above. There is plenty of room (about 3') above the ceiling to hang as needed. So is the best method to hang them from the joists, and if so how? Do you know of any internet site that shows this above a suspended ceiling?

The electric code requires these fixtures to be affiexed to the ceiling grid, period, as Per NEC 2008 Section # 410.36(B).


This is a must.

It will be BOCA, IBC, or whatever building code in effect in your area that may require independent support to building structure.

We clip the fixture to the ceiling grid, many fixtures come with clips or wngs for this purpose, then use jack chain, or #12 ceiling wire to support the fixture loosely to the building.

TK Russell is correct:

1. Screw the fixtures to the grid, using self-tapping sheet metal screws, or use the special clips supplied with the fixture.

2. Usually, there is a small eyelet on the corners of the fixture. Use these eyelets to attach ceiling wires or chains to secure the fixture to the structural ceiling. (This removes the fixture's weight from the ceiling grid.)

Your local building code will tell you how many places you have to support the fixture. Most localities require two opposit corners, but some require all four corners.

At my church, they're just screwed to the grid.