By now I have become somewhat of an expert on light fixture installation, but this one was a doozie.
When I removed the old light fixture, I discovered that it was just merely attached to the drywall and not a junction box. This new fixture required one, so I went to Menard’s and purchased one. When I went to install that, it became even more of a jungle. There was the layer of drywall and underneath that a layer of 1/2″ OSB (Oriented Strand Board). It had to be removed by means of a reciprocating saw. Because of the vibration of the saw, more drywall than what I wanted fell off, leaving a not so pretty site where the fixture is mounted.
You can’t see it unless you’re right underneath it, but it’s going to drive me crazy until I fix it.