Secondary Area (BIA)
What does it mean?
Secondary area (BIA, biarea) consists of spaces that complement the living area but are not counted as primary living space. This includes basement rooms, garages, heated storage, and below-ground spaces used for living. BIA is measured according to the same Swedish Standard (SS 21054:2020) as living area.
For housing seekers, understanding the difference between BOA and BIA is important, as they affect property price and usability differently. A large BIA can be valuable as basement storage or hobby rooms, but is normally valued lower per square meter than BOA. When purchasing houses, BOA and BIA are reported separately, while rental apartments are primarily priced based on BOA.
Key Points
- Encompasses below-ground spaces and supplementary areas outside the living area
- Measured according to the same standard as BOA (SS 21054:2020)
- Includes basements, garages, heated storage, and hobby rooms
- Normally valued lower per square meter than living area
- Reported separately from living area in property listings and tax assessments
Practical Tip
Always check whether advertised area refers to BOA, BIA, or total area. A basement apartment with 40 sqm BOA plus 20 sqm BIA is not comparable to an apartment with 60 sqm BOA. Verify which spaces have been classified as secondary area — sometimes misclassification can affect price or rent.