Walls and Ceilings - Need to secure electric box in ceiling

Hello,
I recently replaced a light fixture. I guess it was too heavy because a thin crack appeared in the plaster about 5 months later across the ceiling where fixture was attached (the kids constantly jumping in their room above didn't help either!).

I took the (heavy) fixture down but would like to put it back up.
Can someone please tell me how to secure a box in the ceiling that could hold a heavy light fixture. If possible I would like to avoid making big holes in the ceiling. The floor above is a finished bedroom (carpeted on top of wood floor).

I am attaching a photo of the current electric box between the joists.

Thanks.

http://i571.photobucket.com/albums/ss154/mdreiff/DSCI2505_1362.jpg

One of the arms on the box isn't attached to anything. It goes half way across & stops. There is no support. A 2x4 across the span would do the trick. Then you don't need the arms. You can bolt the box to the 2x4.

Also, a box for a heavy fixture should have 8/32 screws instead of 6/32. What does that box have?

Thanks for the response.
I am not sure what size screws are being used. I will check.
It's too bad that only now, after the ceiling crack, that I see that the support only goes half way.

Is it possible to get a 2X4 inserted without making a hole much larger than the current one? Are there any other methods, like an extending arm or something that could be used to avoid patching a large hole?

Thanks.

You have enough room to use a ceiling fan support...bout $12-14 anywhere that sells fans. If it will hold a fan, it should hold most any light.

Something like this...http://www.homedepot.com/catalog/productImages/400/56/567c61e2-e2a8-4b59-a0ab-a2081db37b94_400.jpg
Westinghouse Saf-T-Brace Support Brace with Locking Teeth - 0110000 at The Home Depot (http://www.homedepot.com/Lighting-Fans-Ceiling-Fans-Specialty-Parts-Accessories/h_d1/N-5yc1vZ1xkxZarns/R-100351561/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053)

What gunguy posted is what's usually used. Measure the distance first. It looks larger than the normal 16" to me. I don't think you'll be able to mount it without enlarging the hole. How did you get in there to take the picture?

The joists are 14.5 inches apart.
I took the picture from an adjacent room that currently has no ceiling. It's about 6 feet away from the box (i used the zoom on the camera -i just love digital cameras for stuff like this).

Is it possible to screw something into the underside of the floor above. For example attach 2 (or 4) el brackets to a 6 inch 4X4 and attach them to the underside of the floor. Then attach the electric box to the 4X4. That way I don't have to make a huge hole. Or is that idea just wacky?

Is it possible to screw something into the underside of the floor above. For example attach 2 (or 4) el brackets to a 6 inch 4X4 and attach them to the underside of the floor. Then attach the electric box to the 4X4. That way I don't have to make a huge hole. Or is that idea just wacky?
Reply With Quote You don't need to. There is a center screw that holds the current box. You remove it from below. That allows you to remove the box and bend the hanger out of the way from the existing hole.

The box detaches from the new fan support and the hanger installs from below. It contains a threaded rod. As you twist the tube the rod extends our. You finish with a twist of a wrench to be sure it is tight between the joists then mount the new box. It is intended to be installed without enlarging the hole.

This is really a question for the electrical forum but since your getting good answers no reason to repost.

If the joists are 14.5" apart, the box gunguy posted, or something similar is fine. Great camera work.

Also, there are what's called Medallions to cover a larger hole, if you have to cut it.