Living Area or Usable Area?
In Switzerland, there is no uniform method for calculating living area. There are two different standards: the 'main usable area' according to SIA Standard 416 and the 'net living area' as per the WBS/SEL of the Federal Housing Office (Bundesamt für Wohnungswesen/Office fédéral du logement).
Definition: Living Area
The net living area includes all walkable and usable floor spaces with a minimum ceiling height of 1.5 meters. These spaces must be heatable and habitable year-round. Storage rooms, pantries, and similar spaces also count towards the net living area.
Rooms that do not serve residential purposes are not included in the living area. These include unheated rooms, terraces, balconies, outdoor areas, and additional spaces like garages or attic and basement compartments.
When calculating the net living area, wall cross-sections are not included. However, wall cross-sections are counted as part of the gross living area.
Definition: Usable Area
The usable area consists of the main usable area and additional usable area.
The main usable area includes the total area of all rooms in an apartment, including spaces occupied by bathtubs, kitchen appliances, and built-in wardrobes. Basements, attics, and garages are not counted in this calculation, nor are balconies and terraces.
The additional usable area includes spaces such as laundry rooms, attics, basements, storage rooms, shelters, and refuse rooms.
Weighted Area (Surface Pondérée)
The "weighted area" (surface pondérée) is an area specification used in French-speaking Switzerland for the sale of condominium properties. In addition to the regular living area, additional spaces like terraces, balconies, and garden areas are included in the weighted area with an area-specific weighting factor. For example, balconies are weighted 50%, terraces 30%, and garden spaces 10%.
