2 Questions

[jmsbrush]

I have a build out that has a ceiling that is around 18 or 20'. The ceiling's have dry wall up there. The finished product will have a drop ceiling around ten foot.
I have never seen this before. What I have seen through the years. Is just the red iron up above then they hang their wires to hold the drop ceiling.

So here is my question? On my 2x4 t bar lay in fixtures. Where do I tye off my support wires up above if it is a drywall ceiling 20' in the air?

The fixtures have premaid whips on them that are 6' long. The space between the lights are 9' long. So that means I have to drop a box down from the dry wall ceiling thats 20 ' up, with a piece of all -thread in between the lights. Thats seems a little flimsy. Does anybody have some good Ideas they can share with me?

 

[chris kennedy]

Caddy/Erico has lots of cool stuff.

 

[iwire]

I have a build out that has a ceiling that is around 18 or 20'. The ceiling's have dry wall up there. The finished product will have a drop ceiling around ten foot.

That is a major pain and I have only run into it a few times.

Make sure you get in there before the grid goes up.

So here is my question? On my 2x4 t bar lay in fixtures. Where do I tye off my support wires up above if it is a drywall ceiling 20' in the air?

We bought Screw eyes that had a drill tip, we placed a large fender washer on that then drilled them into the perlins that where behind the drywall, yes, that is as much of a pain as it sounds, in my case I was in after the grid so we used a long pole for doing this from a ceiling company and placed that in a drill.

The fixtures have premaid whips on them that are 6' long. The space between the lights are 9' long. So that means I have to drop a box down from the dry wall ceiling thats 20 ' up, with a piece of all -thread in between the lights.

Look at the Caddy / Erico web site and see what products they have. I can tell you I would not be using all thread I would be using 12 AWG ceiling tie wire, yes it is flimsy but it is legal and is the only economical way to do it. (IMO)

 

[frizbeedog]

.....The fixtures have premaid whips on them that are 6' long. The space between the lights are 9' long.

You can install a box on dedicated support wires using these.

Place them in a location that the fixture whip will reach. They also make similar clips for supporting conduit and cable.

 

[cadpoint]

I have a build out that has a ceiling that is around 18 or 20'. The ceiling's have dry wall up there. The finished product will have a drop ceiling around ten foot.

This is an obtained fire rating by enclosing the ceiling super structure.
It could also be a client/owner thermo/heating application.
I'd pay attention to anything that has to do with any required conduits that have to pass through this existing construction!
I'd be sure to install everything back to original construction.

So here is my question? On my 2x4 t bar lay in fixtures. Where do I tye off my support wires up above if it is a drywall ceiling 20' in the air?.

Surely they didn't paint all this > ? Your classis stub finder will aid you greatly if you can, snap some chalk lines _ | _ |_ |

The fixtures have premaid whips on them that are 6' long. The space between the lights are 9' long. So that means I have to drop a box down from the dry wall ceiling thats 20 ' up, with a piece of all -thread in between the lights. Thats seems a little flimsy. Does anybody have some good Ideas they can share with me?

Your drop is 10' or less, on boxes you can drop down with 1/2" conduit (or your desired size threaded rod thread only), or just 3/8 rod. (* your desired size) I've dropped all the way from the ceiling, I've also installed floating all of the branches, it all depends on the situation.
If you float it you've been advised that every other trade will be hanging to it as construction goes forward.
Depending on light layout you could pair up a box to two lights or even four pair them. you've have to make sure by doing a tissue layout, and some mind math, IE Trig.

Now with the * rod off of a toggle bolt and washer backer to ceiling, I'd cross brass to ceiling using either another 3/8" bent with a bender and attached to ceiling. I've had inspectors say that you can't bend rod, well ok, I don't practice it, but I've also installed offset rod.
Or use a 1/2" stick of conduit to within 35" of box as a cross brace off of vertical drop of pole back up to ceiling |/ or \|/. I've used just a rod and .1/2" of conduit and just rod, but our AHJ over two feet ones required to have a conduit over the rod.
Make sure to use the proper strapping in which ever application you come up with and as always a quick reference to the AHJ and consideration of the existing conditions of why that ceiling is there all might be in play.
I think they will want the ceiling to remained sealed but I've seen it blown apart from construction.

 

[mdshunk]

Hang your tie wires NOW. Try to get a different color than everyone else is using. Reason being, some of them will get used, and you'll have something to grip about if all of yours are blue or red, and someone used a blue or red wire for their work.

 

[iwire]

Hang your tie wires NOW. Try to get a different color than everyone else is using. Reason being, some of them will get used, and you'll have something to grip about if all of yours are blue or red, and someone used a blue or red wire for their work.

I generally spray paint my tie wires before I open the bundles, I just flatten out the bundle with my foot and spray them with 'upside down' paint.

Kind of an NEC requirement anyway in fire rated assemblies. 300.11(A)(1)

 

[Pierre C Belarge]

So here is my question? On my 2x4 t bar lay in fixtures. Where do I tye off my support wires up above if it is a drywall ceiling 20' in the air?

The fixtures have premaid whips on them that are 6' long. The space between the lights are 9' long. So that means I have to drop a box down from the dry wall ceiling thats 20 ' up, with a piece of all -thread in between the lights. Thats seems a little flimsy. Does anybody have some good Ideas they can share with me?

There is no NEC requirement to support the layin fixtures from the structure, as long as the ceiling being installed is listed for the fixtures 410.16(C)...most all ceilings are listed for the fixtures. Of course you may have a local law that requires this, if so it is required to be in writing.

In NY, the building code does not require this either. I do not know if that is so in Florida. People just saying so does not mean it really is, take a look at the building codes/local laws.


This will be tougher to comply with. If you use tie-wire to support the boxes/cables, do not forget to look at 300.11(A) -the last 2 sentences and 314.23(D) & (D)(2).

 

[jmsbrush]

Look at the Caddy / Erico web site and see what products they have. I can tell you I would not be using all thread I would be using 12 AWG ceiling tie wire, yes it is flimsy but it is legal and is the only economical way to do it. (IMO)

are you talking about the support for the boxes?

You can install a box on dedicated support wires using these.

Place them in a location that the fixture whip will reach. They also make similar clips for supporting conduit and cable.

Do those work fairly well?

 

[frizbeedog]

You can install a box on dedicated support wires using these.

Place them in a location that the fixture whip will reach. They also make similar clips for supporting conduit and cable.

Do those work fairly well?

Given what you describe, they work great.

I'm a Caddy junkie.

:smile:

 

[iwire]

are you talking about the support for the boxes?

Yes, ceiling tie wire and Caddy products but to comply with the NEC it must be secured at both ends.

I never said it would be pretty or something you would take pictures of for the office walls. :smile:

 

[Cow]

When you install the troffers, how many light whips will reach a box centrally located between them, 2, 3, 4?

If only two, I'd consider ripping the whips out and making homemade whips out of MC and daisy chaining them.

Now, if you can get 3 or 4 factory whips into a box then it's probably worth the trouble to hang a box off tie wire/all thread etc and whip into that.

I would definitely get one of those poles Bob was talking about, we have one, and it worked great when we had a hard lid 10' above the drop ceiling on one of our jobs.