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mtnelectrical
05-22-2009, 12:29 AM
Is there any building code concerning on the installation of luminaries in suspended ceilings? What gauge of steel wire to use for the luminaries in suspended ceiling? how many supports? ( each corner or just two?)

Pierre C Belarge
05-22-2009, 12:41 AM
In general, this is not addressed in the building code. There may be local codes, but not in the ICC.
I spent hours looking for it in all of the documents of the codes, there are 8 books.

It is addressed in the NEC. Typical suspended ceilings are listed to support the fixtures and other appurtanances, such as speaker, vents, etc...
If the ceiling is listed (99% are), then securing the fixture to the ceiling grid as per 410.36(B)- '08 NEC, 410.16(C)-'05 NEC is all that is required.


*Remember local codes may supercede the NEC*

ericsherman37
05-22-2009, 01:30 AM
...appurtanances...

Word of the day!

Pierre C Belarge
05-22-2009, 07:47 AM
Word of the day!
The things we learn when reading a code book.:grin:

Karl H
05-22-2009, 09:07 AM
Here in California it's based on weight. Fixtures weighing less than 56LBS.
To be supported with (2) slack 12GA. safety wires at diagonal corners.

Fixtures weighing more than 56LBS support with (4) independent taut 12GA.
wires attached to the structure above. Each wire must be capable of
supporting (4) times the weight of the fixture.

mtnelectrical
05-22-2009, 09:51 AM
What about securing the wiring? Bat wings is what we use but Have your ever see wiring secured to the steel wire by cable ties?

cowboyjwc
05-22-2009, 10:15 AM
You need to look at the CISCA standards (Guidelines for seismic restraint for direct hung suspended ceiling assemblies).

To answer your question:

Fixtures weighing less than 10 pounds shall have one #12 gage hanger wire.

Fixtures weighing more than 10 pounds, but less than 56 pounds shall have, in addition to the requirements outlined above, two #12 gage hanger wires.

Lighting fixtures weighing 56 pounds or more shall be supported directly from the structure above by approved hangers.

Karl H
05-22-2009, 08:05 PM
You need to look at the CISCA standards (Guidelines for seismic restraint for direct hung suspended ceiling assemblies).

To answer your question:

Fixtures weighing less than 10 pounds shall have one #12 gage hanger wire.

Fixtures weighing more than 10 pounds, but less than 56 pounds shall have, in addition to the requirements outlined above, two #12 gage hanger wires.

Lighting fixtures weighing 56 pounds or more shall be supported directly from the structure above by approved hangers.

Didn't I just say that in post #5? :D

Karl H
05-22-2009, 08:08 PM
What about securing the wiring? Bat wings is what we use but Have your ever see wiring secured to the steel wire by cable ties?

We use "Bat Wings" here,BUt we are only allowed to support the fixture's
circuit or E-ballast circuit to the the fixture wires. Everything else gets it's
own wire attached to the structure above and to a "Banna" clip to the
grid.

mtnelectrical
05-25-2009, 06:01 PM
sorry but that name is new to me. what is a banana clip?

electricalperson
05-25-2009, 06:16 PM
i just use jack chain to support the lights

active1
05-25-2009, 08:48 PM
Banana clip:

http://www.erico.com/public/library/Fixing/LT1458.pdf