Hanging a 200lb chandelier

[green2012]

I have never hung something this large. I am erecting scaffolding to get up the 18foot ceiling. I am going to put a piece of double strut across 2 ceiling joists and use threaded rod to support the fixture. I guess my question is weather or not the ceiling joists are rated for that weight. I wouldnt see why not but figured Id ask. Should I go across a few joists to spread the weight? Whats best practice?

 

[GoldDigger]

I have never hung something this large. I am erecting scaffolding to get up the 18foot ceiling. I am going to put a piece of double strut across 2 ceiling joists and use threaded rod to support the fixture. I guess my question is weather or not the ceiling joists are rated for that weight. I wouldnt see why not but figured Id ask. Should I go across a few joists to spread the weight? Whats best practice?

What size are the ceiling joists and is the space above them accessible? They may be rated for a high load per square foot if the attic space is intended for storage, or just enough to suspend the drywall if the roof load is carried entirely by trusses.

Without doing an engineering calculation for your exact situation, I would say that the joists must be rated to support a 200# plus worker walking on them, so you should be OK.

Make sure that the strut is attached to the joists and not just resting on them.

 

[green2012]

There is access above the space but I need to cut into it first. Its not intended for storage because they sealed it off. not sure of the size of the joists or weather its intended just for the drywall. Is there a way to look at it and tell?

 

[GoldDigger]

Is there a way to look at it and tell?

Well, yes, sort of.

Look at
1. The size of the members (2x4 minimum, more likely 2x6 or even larger) If they are 2x6 or larger they are pretty definitely capable of extra load.
If they are 2x3 or smaller, they are just framing for the drywall, so see Note.
2. The horizontal spacing between them. (probably 16", but might be 24")
3. The unsupported span between vertical load bearing support points of each member (might be full length of member or from load bearing wall to load bearing wall)

Note: a sheet of 5/8" drywall weighs about 2.5 #/sq.ft., so a 200 # concentrated point load can be a lot more than expected.

On the other hand, building codes will, AIR, require a structural ceiling even if there is a "drywall-only" cosmetic ceiling below it.
Depends on how old the construction is. With a very old house I would be more cautious.

Assume that at some point the mount will have to support the chandelier plus a 200# homeowner hanging from it because he or the ladder slipped while changing a light bulb.

 

[zbang]

Dead (fixed) hung? That's a nightmare for changing lamps and cleaning. Can you sell them a powered winch?

 

[GoldDigger]

Dead (fixed) hung? That's a nightmare for changing lamps and cleaning. Can you sell them a powered winch?

Maintenance accessibility depends on how high it ends up. If hung so that the lampholders are only 8' above the floor it is almost reasonable. (I have cleaned the prisms of a chandelier at the 8' level working from a stepladder, and I did not feel unsafe.)
A powered winch may end up costing as much as the chandelier.

 

[SceneryDriver]

green2012,
I work in the entertainment industry, designing and building special effects and theatrical automation. I also rig and fly performers; think Peter Pan, and the like. I see and use rigging on an almost daily basis; please PLEASE PLEASE involve a structural engineer and a rigging expert in this endeavor. 200# is more than enough to severely injure or even kill someone.

Where are you located geographically? Is seismic loading a concern?

Please understand I mean no disrespect when I say this: well-meaning electrical contractors, while being exceptional at their jobs as electrical professionals, are not riggers. I have worked in more than a few entertainment venues where the EC got the bid to do the rigging, and the results were pretty uniformly a mess.

Rigging and the suspension of heavy things over people's heads is a specialty and art form unto itself. If you can't define and use terms like "ultimate breaking strength," "minimum breaking strength," "design factor," "dynamic load," and the actual, legal meaning of "rated hardware," it behooves you to enlist the help of a specialist. It's often more involved than simply bridging some rafters with Unistrut.

Where are you located geographically? I may be able to recommend a company in your general area that might be able to help. Failing that, try a search for "theatrical rigging companies" on Google.

I've seen the aftermath of rigging failures; messy, expensive, and sometimes deadly. You owe it to yourself and your client to do this correctly. Knowing that something won't fail is much different than knowing it hasn't failed yet. Gravity is a demanding mistress, and will not be ignored.



-SceneryDriver

 

[barclayd]

green2012,
please PLEASE PLEASE involve a structural engineer and a rigging expert


-SceneryDriver

I heartily agree with Scenery Driver.
db

 

[handy10]

If the ceiling is held up by trusses, the load is almost certainly too much. You can usually recognize a truss because they are constructed with 2x4s and steel gusset plates; trusses are usually placed 2' on center. I echo the advice of getting a structural engineer to approve the project.