We were asked to repair a dropped ceiling in a bathroom in an older home. It appeared that the ceiling had gotten wet at some time and was sagging because of the moisture. When we started opening the ceiling to do the repair, the whole ceiling fell in. A lot of debris was piled onto the dropped ceiling. We removed all the debris from the bathroom and cleaned up the mess. What we found in the debris was a section of an old cast iron plumbing stack. Apparently the stack was replaced at some time and whoever did the work left a section of the stack along with other debris sitting on top of the suspended ceiling. It’s fortunate that nobody was hurt when the ceiling fell in. It just made a big mess.