Hanging Chandelier by Threaded Rod

Question

I recently bought a large, heavy chandelier (~75#, 52" diameter, two tiered) to replace an existing fan in my great room.

The instructions state:

A 1/4 IPS Pipe must be installed through the junction box and secured to a structural member of the building. This item must hang independently of the junction box. Then install the threaded nipple into the 1/4 IPS pipe."

It's easy enough to find a mounting plate or threaded rod hanger, but securing it independently of the junction box seems like overkill, and a pain. I would probably have to go into the attic and put some strapping between joists so I could center the pipe, since the current junction box is not in between joists. I think attaching the chandelier to a heavy duty junction box with a mounting plate for the threaded rod should be fine. Anyone have any thoughts or experience with this?

Answer 1

I suspect the point here is to have a redundancy.

If for whatever reason the jb were to rip out of the ceiling there would be a secondary mechanism that prevents your 75# light from falling and killing someone.

Almost all heavy items like this have a secondary restraint. That said contractors often find it too much of a pain to install as well. I guess it isn't their life on the line.

Answer 2

The only time I would chance using an existing box would be if it is a fan rated box.

75 lbs is a lot of weight and many boxes are only “tagged” in with 16 penny nails I use the term tagged as they are just holding the box with an inch if the nail sticking into the joist.

With something that heavy make sure the box is listed for the weight or add the additional support.

Edit: per the edit of a heavy (225 lb box and a secondary cable) I would put my license on the line as this is similar to many commercial fixtures even ones in Gymnasiums where the fixtures get hit hard enough to break the lamps but the restraints have always held the fixture from coming to the ground.

Answer 3

The junction box is not there for mechanical support. It's made to enclose electrical connections and you shouldn't expect it to be mounted in such a way to support more weight than that.

What does "heavy duty junction box" even mean anyways? That's like arguing that a heavy duty extension cord is suitable as a rope because it's heavy duty.

Answer 4

You're going to have to remove the box and replace it. No box I know of that is secured to a single stud will support 75lbs. That's almost certainly why they want extra support; they're assuming you have a basic plastic box you cannot replace (which is most lighting installs).

What you want is a metal box with a metal support arm. You might even have to move your box hole.

This particular one is rated for 150lbs between 16" studs.You screw the brace into place, and you can see it hits both studs, allowing it to support the weight.

The alternative would be mounting a board (like a 2x4) above the hole and attaching a metal box to it (that assumes you have access from the attic side). As long as the box says 70lbs for a ceiling fan, it should support a dead weight 150lbs basic lighting fixture.

Whatever you do, do not use a plastic or fiberglass box for this job. None of them are rated above 50lbs.

Answer 5

If the rod is attached by a box stud to the back of a metal box that is in turn fastened securely to the structure it should be fine for 75 pounds.

In other words I would regard the back of a metal box as an adequate way of following the instructions to secure the rod to the structure, if done purposefully.

Almost every word above is important. I don't know what you mean by "mounting plate" or"heavy duty" but I would not use anything that relies on the box cover ears, which is what pretty much every new mounting system does, or any non metal box, any box mounted with nails up into a joist or mounted in an unknown way, or any box mounted on one side only to the side of a joist, etc etc ...