I put laminate flooring down, both over the tub, and toilet. I know most would not approve, and I was sceptical, but was told that if I ran a bead of silicone around the perimiter (hidden by the baseboard) and not leave water for an extended amount of time it would be alright. I even ran silicone where the floor met the toilet flange, just in case I had a wax ring go bad. I haven't had any problems thus far, and it was inexpensive to do.I also did not run it fully under the tub, just in case it did have to come out, the new floor could still slide under the tub. I'm sure some will disagree with my decision, but it has worked out.