Living room, bedroom, children's room and study are counted as whole rooms. The bathroom, kitchen and hallway are not considered rooms. There is no legally valid definition for half rooms in Switzerland, but the following custom has become established: Naturally lit and ventilated areas that cannot be counted as rooms are considered half rooms if there is a large eat-in kitchen of 12 m2 or more, a dining area of at least 6 m2 in the kitchen, or an anteroom or hallway with an area of at least 6 m2.