Sounds similar to my house,, well, almost, anyway, I use
- one level for ground (=garden, with low walls as foundation)
---+ mid level for bathroom (a few cm up from the ground)
- one level for "ground" floor (floor where walls continue...)
---+ and in your case, mid level, for the kitchen 30cm up (no walls on this level)
- one level for first floor
Point is, you can have your main levels - floors - where walls meet vertically, AND then you can insert "in-between" levels for each floor / walking surface. Remember that you can use negative elevation if your bathroom really is a pit...
ok
