Creating rooms without a wall

[voldan]

My dining room and living room do not have a wall between them but I would still want to create different rooms for them (for different floor tiles, to see the area etc.)
However, to create a room you have to have walls on all sides...
I was wondering if there was a way around it (I tried to put a wall 0.5 cm high but you can still see it both in the 2D view and the 3D view and I don't want to see it...)
Thanks

[Puybaret]

Double-clicking is a shortcut to create rooms surrounded by walls, but you can create any surface by simply clicking at each corner point of that surface.