What if the metal support bracket that spans between the joists is drilled and tapped with 10-32 srews and the fan is supported by that? Would that not qualify as being independently supported from the box?
As far as the code that would be a judgment call.
I would not trust those metal supports because all is mounted with is probably couple of drywall nails.
Im not so sure that would have any less strength than using one of these.
I've replaced the original bar with these and the original bar seemed to have been more secure.
![[Linked Image from i95.photobucket.com]](https://i95.photobucket.com/albums/l129/brucepri/FanBraceBox.jpg)
Grab a hold of the bar and lift yourself off the ladder. It it holds you're ok. If not, well you've got some drywall to patch.
