On 9/28/2015 5:35 AM, DerbyDad03 wrote:
I spent the weekend helping my Dad prepare his house to be put on the market.

One of the tasks was to remove the light fixtures from a bathroom. After
removing the fixtures themselves, I was left with the mounting plates shown
in the following picture.

http://i440.photobucket.com/albums/q...pssjkqsr1x.jpg

When I removed the plates I found that the electrical boxes were not attached
to the studs, instead they were attached directly to the back of mounting
plates using a threaded tube and strap, similar to this setup:

http://i111.photobucket.com/albums/n...j/DSC03039.jpg

The threaded tube came through a hole in the center of the mounting plate
and was secured with a nut. The mounting plates themselves were screwed
through the wallboard into a stud. Obviously, when I removed the plates, the
electrical boxes came out with them.

Is this an acceptable method of installation?

First impression was to say, "No". Boxes want to be secured, Romex
wants to be anchored to a stud near its entrance into box, etc.

But, after thinking about it, ceiling (exhaust) fans are constructed
the same way: box is part of fan and supported by the fan. The
same is true of "remodel" style recessed can lighting. etc.

So, probably would get past a reasonable inspector. OTOH, you
may want to change the installation going forward.