My work in progress to make my Dolphin a rolling palace. You will notice the gray addition on the floor. I had a spot that was a bit rotted and sagging. I couldnt replace the floor due to inaccessibility so I poured a non concrete leveling compound on the floor. As I was screwing a really hard wood over the top of the whole thing, I knew that would tie the entire floor together. I just needed to fill the sag.