yes the floor slopes, the floors and walls have a waterproofing membrane under them

Love how you integrated the comment and the wood design.
So for the bathroom, the membrane was put under the entire room, before the concrete slab was poured in place? Or is it on top of the slab with another concrete finish added on after the fact?

How was the pitch to the drain achieved? Was it achieve during the poor or ground out afterward?

Beautiful by the way!