The new shower in the master bath has a mud floor. I've seen it done on television, and I knew I wanted no piece of that. Frank, the contractor, brought in a special mud floor guy, and he knocked it out in no time. A plumber also repositioned the showerhead to the middle of the new space and rasised it a bit. As an interesting side note, it turns out that the existing drain wasn't attached to a pipe of any sort... just a hole in the floor.