# cable supports



## Bulldog1 (Oct 21, 2011)

You can't use the ceiling grid tie wires. You have to install your own and paint them to identify them from the ceiling tie wires if I remember correctly. You can screw them to the grid if you screw into the main runner. Fire or building code I believe.


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## tkb (Jan 21, 2009)

All Current said:


> Was curios if it was still permissable to support mc cable from existing Hung cieling wires. We use to use an approved caddy clip for this application. Also is it still permissable to screw the lay in fixture to the actual cieling grid? Thanks in advance
> Is this a fire code issue?


No and it hasn't been permissible for many years, see 300.11(A)(2)


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## Amish Electrician (Jan 2, 2010)

The citation to 310.11 is a bad citation.

"Quite some time" is a bit subjective. Since Caddy, Erico, and others continue to make hardware specifically designed to support cable, conduit, and boxes from suspended ceiling grid, the issue deserves a closer look.

As recently as the 1999 NEC, we were allowed to attach to the grid, or it's support wires. See 370.23(d) and 410.16 of the 99 NEC. One qualification was that this could not be done if - and it's a big IF- the suspended ceiling was part of a fire-rated floor/ceiling assembly; then you had to look to the assembly specifications.

There's also the complicating detail of earthquake requirements in many areas.

As a general matter, we now have to run our own support wires, anchor those wires to the building structure AND to the ceiling grid, and can forget about the area above the grid ever being 'accessible' again. 

Let's face it: There are so many support wires and so much stuff 'above the grid' that you can forget ever being able to simply pop a tile out for access.


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## don_resqcapt19 (Jul 18, 2010)

You still can use the grid support wires if you can get instructions from the ceiling manufacturer telling you how to do it.


> _Exception: The ceiling support system shall be permitted to support branch-circuit wiring and associated equipment where installed in accordance with the ceiling system manufacturer’s instructions._


_
_


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## tkb (Jan 21, 2009)

Amish Electrician said:


> The citation to 310.11 is a bad citation.
> 
> "Quite some time" is a bit subjective. Since Caddy, Erico, and others continue to make hardware specifically designed to support cable, conduit, and boxes from suspended ceiling grid, the issue deserves a closer look.
> 
> ...


I don't know how you figure 310.11 is a bad reference.
The OP did not say that the ceiling was fire rated or was permitted to be used as supports by the manufacturer.

Just because a manufacturer makes a product it doesn't mean that it is code compliant to use it in all situations.

If the new support wires were added responsibly, the ceiling tiles would be able to be removed as easy as they were before the new wires were installed.

He asked a general question and got a general answer.
The majority of suspended ceilings are not fire rated assemblies and you would be hard pressed to find a manufacturer that would allow support of anything from their system without evaluating it first.


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## Amish Electrician (Jan 2, 2010)

I said 310.11 was a bad reference because it doesn't check out in either the 2008 or 2011 NEC. It doesn't exist in one, and has nothing to do with support in the other.

Considering the amount of revision this section has had in the past several editions, I would not be surprised if it's a good reference somewhere.

As for adding wires not affecting tile removal, I beg to differ. I've been through that in 'quake country,' and EVERY clip and wire makes it just a bit harder to remove the tiles. It adds up- to where it's pretty darn hard to remove tiles without damage- especially if that tile has been removed a few times already.


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