My first wetroom!

[White Room]

Agree with Localtiler, actually wedi board, jackboard, marmox board are waterproof but plasterboard and aquapanel are classed as water resistents. You can also look for medium rangers like NMP or hardibacker boards. With Hardibacker you can also make holes for soap dishes or hooks, as it is easy to cut.

I wouldn't class it as water resistant, it will suck up moisture like a sponge.