Stick this one under "stupid dumb things the GC did." While roughing in a new house one winter month, the GC got the bright idea to place a piece of sheetrock (wallboard) over an opening in front of a fireplace where the hearth was suppose to go. All was alright until another installer who was new to the job step off of a six foot ladder thinking that the sheetrock was on solid ground. He fell through the floor to the floor down below. Luckily, he didn't get hurt real bad. He could have broke a neck or leg, but luck was with him. Once he got up, he let the GC have it. I thought he was going to throw the GC down the hole.