We count as room: the bedrooms, the lounge, the dining room, the study. We don’t count all the ‘’technical’’ places of the house: kitchen, bathrooms/toilets, cave, attic, place for the heating system, etc …. A main room must have between 9 M2 and 40 M2. We don’t count a room with less than 9 M2 (for example a small study or small bedroom). We count for 2 rooms a more 40 M2 room (for example a large lounge).