luminaire support in suspended ceiling

[grandpa]

1. Is there any requirement for a specific type of wire to support a lay in "troffer" style fixture in suspended ceiling systems?
2. Can the fixture support wires be attached to the eye lags or bolts that support the ceiling system or must they have their own anchors?
3. Are there clips that accomplish this support and negate the need for wire support?

 

[Dennis Alwon]

I don't believe the NEC addresses that however there may be a local ordinance that requires a separate attachment

 

[JFletcher]

1. Is there any requirement for a specific type of wire to support a lay in "troffer" style fixture in suspended ceiling systems?
2. Can the fixture support wires be attached to the eye lags or bolts that support the ceiling system or must they have their own anchors?
3. Are there clips that accomplish this support and negate the need for wire support?

1) Not to my knowledge
2) I would think so, however the lags may not be mfg rated for more weight than what they are already carrying
3) If you are thinking about clipping the troughs to the grid for support, in most cases the grid is not rated to support anything except itself. You can use clips; 410.36*.

If the deck is wayy above the drop ceiling, you can use an extension tool to shoot in (assuming it's a concrete deck) clips with your own tie-wires.

You're asking more about local building codes than NEC. There are two questions: 1) is the grid a fire barrier or not and 2) is it mfg rated to support lights. Even if it isnt a fire barrier and is mfg rated to support luminaires, local codes may require you to independently support all of your troffers.

*I've read some FDs do not want the troffers clipped to the grid, reason being if they have to tear it out with a fire axe, the troffers dont come down with the grid. this is also why anywhere Ive worked the lights have to be independently supported regardless of the grid type.

 

[luckylerado]

I think this has a lot to do with the seismic category and the weight of the fixture. There is a lot of good info here:

CISCA Seismic Construction Handbook

 

[david]

the design professional who laid out the ceiling grid system should be aware of the lighting system (weight) and you would think he spec. the size wire and distance of support wire for the ceiling grid system including lighting fixtures.

The only thing that should be required is the fixture securely fastened to the grid, unless the designer specified additional support wires for the lighting fixtures.

What if any does the design call for in support for the fixtures?

 

[grandpa]

In this case, nothing spec'd out. It's a boiler plate set of plans for a chain store tenant improvement. We were just having a lively in house discussion about this in our office and came to the forum for additional input.

 

[JFletcher]

I read elsewhere that if the troffer weighs more than 56lbs, the support wires have to be 12ga. I havent seen any troffers, even with battery backup, weigh close to this, but there you go.