I am interested in making an entire 8x8 bathroom into a shower floor. I believe this is called a "wet room." I would mount the toilet on a raised pad/curb. The sink would be mounted to the wall.

The point of this is to have a wide open, versatile, upgradeable, power washable bathroom. There would be a shower curtain around the shower, and I am thinking about setting a clawfoot tub in there at a later date, without any hookups, just draining onto the floor. I suppose I would make it so you have to hold the tub-drain open to drain it, so you can watch to be sure it's not backing up on the floor.

My question is, can I make the threshold of the bathroom entry door to be the curb? Basically when entering the bathroom, there would be a 1.5-inch step-down upon entering the bathroom. The rest of the 2-inch required tray could easily be provided with the 1/4-inch floor pitch.

I'm planning to do this job on the cheap, but good, with PVC liner and double mud. I know it's a little non-standard, but I think it might work well and be simple.

Has anybody done this sort of thing? Would I be able to mud that much area (almost 64 square feet) at once? Any other problems I might run into? Opinions?

Thanks, people!

-Aaron