Heavy fixtures

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celtic

celtic

Senior Member
Location
NJ
I have a fixture dilemma I hope you guys can help out with.


How would you support fixtures that weigh in excess of 200# approaching 500#s?

Here's the scenario...
Catering hall with poured floors, steel deck pans, steel beams, etc (20' typically).
Ceiling heights vary, none more than 12'...ceilings are sheetrocked, all metal stud construction.
Within the celings you have your various mazes of elec. and plumbing conduits, HVAC lines and ducts etc.

I have never hung an 8' - 10' spread chandelier of these weights....and the customer has NOT made their final selections of fixtures.

I was thinking of using threaded rods and drop in anchors....all that rod seems rather labor intensive though.
Any thoughts on chain (3/8" or better) or maybe even "aircraft cable" ?

I'm also thinking 4" boxes(square w/ring or octagon) are just for wiring means....but do these giants come with a factory supplied box and/or bracing?

I am pretty much in the dark on this one.....ideas, suggestions, caveats?
 
I would go with the aircraft cable, thats what they use with those aladdin lite kits...


I found these for wire systems, wonder if they have anything for fixtures...?http://www.cablemanstore.co.uk/erol...ff&ie=UTF-8&rlz=1B2RNFA_enUS220US220&q=sld2l2


speedlink01.jpg
 
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Celtic, i would think a 12"x12" x1/4" steel plate with an eye bolt through the center hung with the threaded rod to the deck above would hold 500#.The plate could be adjusted with the rod to the height above the hard ceiling.Most of the special light fixtures that i've seen only come with one point of attachment.You'll most likely need to assemble the fixture on site, so a permanent support will be needed to build off of.
Rick
 
Guys, comeon, I would think that answers that start "I would think" is quite scary when dealing with a quarter of a ton waiting (or should that be weighting...?) to land on someone's head. Liability. Insurance. Courts. Being sued. And hurting people. All bad stuff.

What is it that home owners who post here are told to do? Oh yes, consult a professional, someone who is skilled in the art. That 500lb will need to supported from something rated to take the load, consult a rigger on how to safely suspend that mother.
 
dbuckley said:
What is it that home owners who post here are told to do? Oh yes, consult a professional, someone who is skilled in the art. That 500lb will need to supported from something rated to take the load, consult a rigger on how to safely suspend that mother.
Click to expand...

We are a far cry from HO's asking which way does a lightbulb unscrew.

We are professionals who share their experiences to enlighten those professionals who have run into a speed bump.

Hire a rigger?
I don't think so.
In the course of an EC's job, you move switchgear in excess of 500# .....you pull wires at 5000+# of force.....run 4" RGC 50' feet in the air....lift and set light poles that weigh hundreds of pounds .....and the "riggers" get the bleacher seats.

Come on....
 
So remind me why you are asking the question?

Like you say:

"The more I learn, the less I know."

Consult a professional in the "hanging heavy stuff from up there" business who has appropriate qualifications and experience. And insurance.

Edited to say - or take a risk. You could follow the advice anyone on here could offer, in good faith, and it goes wrong, and then what happens? You can be sure council will have this thread printed out for the court to see... With electrics you can always fall back on the NEC (or an arguable interpretation of), but with non-electrics, you get no such wiggle room.
 
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I have only been involved in one application like this with my old boss. Was about 400 Lbs. The fixture was so heavy and he didn't want the liability of designing his own support system so he made the customer buy a light lift rated for the weight of the fixture. Took the burden off his shoulders I guess. It also took another additional full day to assemble the chandelier :cool:.
 
Heavy fixtures

Celtic I like the idea of you using rods but it is hard to say without seeing or being in that situtation. I also like some of the other answers Also thanks for your second reply I agree. All of us have a (brain fart) sometimes and its good to be able to ask someone else there thought's without being critiized . Have a GREAT day and Semper Fi.Buddy
 
How about one of those motorized lifts for chandeliers. They are made for all different weights up to 1200 lbs.
http://www.lightinglowering.com/pdf/lowering/MLS-spec_Complete.pdf
Edit to add
I agree with the comment about liability and it seems that you may spend more time fabricating something then it is worth. With the motorized system they can easily change bulbs and clean the fixture. Just a thought
 
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We do load calcs, right? No different than that, it's just engineering. If you don't know how to determine how to safely do something, like hang 500# over someone's head, hire someone that does.

(Me, I'd start with checking the working load of the cable and fittings I'd use, and the working load of the anchors...)

Likewise, if it's really approaching 500#, the ceiling/roof structure may not tolerate a point load of that much, which means a structures person needs to determine who/where to hang it.

(This is not the same as moving a switchboard. The chandelier might fall on 4-5 members of the public, and they're probably not wearing safety gear.)
 
If you can get the owner to decide on a fixture contact the manufacturer. They have probably run into this question before. They may have some details to offer. Has anyone run these weights by the structural engineer on the job?
 
Does the structural engineer know about these fixtures?

I'll bet he has some good ideas on how to accomodate the chandelier and may have included them in his design. Check with him/her.
 
Thanks for the replies....still waiting for fixture selection....and sheetrock is being delivered.....it's gonna get interesting real quick.
 
18" square x 1/2" steel plate with 4 3/8" rods supporting the 4 corners. Thru bolt your fixture support to that. The 18" square gets your supports far enough apart to make sure you are not concentrating weight all in one spot on the ceiling structure above. Or you could use two struts set at 90 degrees to each other and bolted one on top of the other as an alternate. Your light fixture is fairly close to hanging a 45 kva xfmr up high. My bet is that if it was a transformer you would have it up there already, but since it is something different, your letting it slow you down.
 
celtic said:
I was thinking of using threaded rods and drop in anchors....all that rod seems rather labor intensive though.
Any thoughts on chain (3/8" or better) or maybe even "aircraft cable" ?

I'm also thinking 4" boxes(square w/ring or octagon) are just for wiring means....but do these giants come with a factory supplied box and/or bracing?
Click to expand...

First remove "drop anchors" from any thoughts on this job. Way too much liability there. I would see about through bolting them to the deck above. Also you'll need them to spec the fixture and stick to it. Slightly smaller ~100lbs come witrh a 1/2 hickey attatchment. I have seen some come with a 1/2" threaded mounting eye, and one 500lbs cast iron nightmare with 7/8" all-thread, you'll need to know all the particulars before you begin...

In the past I have through bolted to heavy framing and through the center KO of a 4 11/16 box with 1/4" aircraft cable safety adjacent. Loctite all but the canopy. However, I would suggest due to the wieght, lamping, hanging and cleaning issues that you add one of these lifts to the job. It just might be a labor savings in the install in the long run. And money saver for the customer too as time goes on. http://www.aladdinlightlift.com/originalproducts.html
 
IMO, consulting with the structural engineer is the best approach. You want to make sure wherever you are transfering the load to is adequate to handle the additional loading.

I've always gone for a 4:1 safety margin.

The comment about knowing what you are working with is spot on. They must decide on the fixture so you can get the support system installed.

Good luck Celtic, please let us know what you wind up doing.
 
I'm not sure what the earthquake situation is like where you are, but you need to consider some amount of lateral bracing as well. Threaded rods give you almost zero lateral resistance. Typically, you're looking at strut at 45 or 60 degree angles in all 4 directions. However, you have to know the lengths of the strut, as they will need to be treated as an unbraced column and may buckle if they aren't stout enough. The fact that you are hanging a chandelier that can swing and oscillate doesn't help with that. If it's unbraced, the thing may or may not fall in an earthquake, but it would take out half the ceiling as it did a "wrecking ball".

Mike (from earthquake country)
 
Good points....thanks all.

"Luckily", the 500# monsters are directly under steel beams....that will allow me plenty of opportunities for attachment.

If they could just make up their minds if the other fixtures are 25# or 250# life would be easier.
 
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