The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!


2017 NEC and Related
2017 NEC
Now Available!

Recent Posts
Sprinklered equipment 26-008
by bigpapa
12/02/16 04:24 PM
On Delay Relay with Auto Reset
by Potseal
12/01/16 09:59 AM
Wow, that was close!
by jraef
11/28/16 07:06 PM
Earthquake in New Zeeland
11/27/16 11:25 PM
Calling all Non-US members!! (Non-US only)
by Tjia1981
11/27/16 06:33 AM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 14
HotLine1 10
Trumpy 8
Texas_Ranger 8
sparkyinak 7
Who's Online
0 registered (), 198 Guests and 5 Spiders online.
Key: Admin, Global Mod, Mod
Page 1 of 2 1 2 >
Topic Options
Rate This Topic
#153599 - 10/21/03 06:42 PM Suspended ceilings
Ryan_J Offline

Registered: 08/19/03
Posts: 1355
Loc: West Jordan, Utah, USA
What does your jurisdiction require for the support of fixtures in/on a grid ceiling?
Ryan Jackson,
Salt Lake City

Building Codes & Related References
#153600 - 10/22/03 03:13 AM Re: Suspended ceilings
iwire Offline

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
410.16(C). Add a second paragraph as follows:
In addition to, or in lieu of, the mechanical fastening means, electric luminaires (fixtures) containing ballasts, other than simple fluorescent reactance ballasts, shall be supported directly to the building structure by wire, chain, or threaded rod of sufficient strength to carry the luminaire (fixture). Fluorescent luminaires (fixtures) shall be supported at each end of a diagonal axis of the luminaire (fixture).

Most times we use 12 awg ceiling tie wire for this, supported by one attachment point, however job specs range greatly.

We have done jobs where the job spec was four separate wires from four separate points of attachment, and this was for a job with all 2' x 2' drop ins.

Also job specs may require attachment to the grid along with the independent supports.
Bob Badger
Construction & Maintenance Electrician

#153601 - 10/22/03 07:11 AM Re: Suspended ceilings
Roger Offline

Registered: 05/18/02
Posts: 1779
Loc: N.C.
Ryan, we are required to support our fixtures to the structure, I am being told that is due to our siesmic situation but can't get a code reference. Some inspectors are requiring all four corners. This is also writen into 90% of job specifications.


#153602 - 10/22/03 07:27 AM Re: Suspended ceilings
Bill Addiss Offline

Registered: 10/07/00
Posts: 4196
Loc: NY, USA

You have a 'seismic situation' in NC?
I don't think I ever heard of any quakes down there.


#153603 - 10/22/03 11:06 AM Re: Suspended ceilings
George Corron Offline

Registered: 05/16/01
Posts: 728
Loc: Lorton, Va USA
When's the last time you heard of VA having an earthquake? But we ARE a Seismic 1 area and therefore required to support to structure.

That does NOT supersede 410 requirements which says we have to support to grid as well. If you don't screw/clip to grid, you always push the light up when changing tubes, so we always required both.

#153604 - 10/22/03 11:18 AM Re: Suspended ceilings
Roger Offline

Registered: 05/18/02
Posts: 1779
Loc: N.C.
Hello Bill, we actualy had one in Alabama that shook me out of bed (exageration ) not to long ago.

Rare Southern quake near Georgia-Alabama
state line rattles several states; 4.5 magnitude

The Associated Press

ATLANTA (AP) -- A 4.5 magnitude earthquake centered in northern
Alabama rattled windows and bookshelves around the South early

The rare Southern quake, which occurred at about 5 a.m., was centered
near the Alabama-Georgia line, 27 miles northwest of Rome, Ga.,
according to the U.S. Geological Survey's Web site.

The quake was felt as far away as North Carolina and Kentucky.
Emergency officials said they had not heard any reports of serious

In Atlanta, about 160 miles from the epicenter, the quake moved dishes
and pictures on shelves.

"My whole house shook, I could feel the whole wave go north to south,"
said Barry Goodno, a Georgia Tech structural engineering professor who
specializes in earthquakes. "Everything was rattling through the room. It
was not what I expected in Georgia.

"It's the kind of motion that could weaken structures or cause further
damage," Goodno said. "It's not something to be overlooked. This could be
a precursor, it could be a one-time release of energy, it could be an
indication of things to come for several weeks."

Carolyn Parker of Gadsden, Ala., says the earthquake lasted about 45
seconds and woke her up.

"At first I thought it was like thunder," she told WSB-TV. "Then it was a lot
heavier. It rattled the windows.

"My husband jumped out of bed. He said he thought it was like the end of
the world or something. He ran outside."

Nick Jebeles of Remlap, Ala., said he and his wife also were awakened.

"I went out on my back porch because I thought it was a tornado, but the
weather was fine," he said.

* * *



[This message has been edited by Roger (edited 10-22-2003).]

#153605 - 10/22/03 04:12 PM Re: Suspended ceilings
gunther Offline

Registered: 09/17/03
Posts: 59
Our inspectors (in Central Florida) only require 2x4 and 2x2 flourescent fixtures to be screwed off to the grid on at least opposite corners or in the middle, unless it is spec'd otherwise in the prints. Is there a specific code reference to cite? I guess I should get out the book and look for myself. In supporting fixtures by grid wire (if spec'd) or supporting fixture whips or feeds, we are allowed to use the same support brackets or hooks that the grid guys hang to tie their wires to. Some jurisdictions (mainly in the city) require the support wires we add to be identified by yellow or orange paint or even just tagged by a piece of colored tape so that it is readily able to be identified by them as such.

#153606 - 10/22/03 04:38 PM Re: Suspended ceilings
Ryan_J Offline

Registered: 08/19/03
Posts: 1355
Loc: West Jordan, Utah, USA
Gunther: I don't have my IBC here at the house, but if you are asking for a building code reference, try IBC 1621.2.5. If you are in a siesmic design catagory D1 or D2 or E, you will need to comply with the "CISCA 3-4" standard, as per the 2000 IBC.

I apologize for not having more for you, I will see what I can find tommorrow.
Ryan Jackson,
Salt Lake City

#153607 - 10/22/03 04:41 PM Re: Suspended ceilings
Roger Offline

Registered: 05/18/02
Posts: 1779
Loc: N.C.
Gunther, the specific NEC article is 410.16(C).

It's interesting that there are no UL assemblies in rated grid ceilings (UL orange books)that require layin fixtures be supported to the structure.


#153608 - 10/23/03 02:02 PM Re: Suspended ceilings
pwood Offline

Registered: 02/04/03
Posts: 64
Loc: castella,calif usa
in caleeforneea it's chapter 25 of the building code and u.b.c.standard 25-2 that describes the installation proceedure.two #12 wires to each fixture at a minimun and they can have slack.any fixture that weighs over 56# must have approved hangers and be supported from above.if it is a listed system you would follow the installation instructions.

Page 1 of 2 1 2 >

ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals