A single-family house is basically a house with a dwelling. There are slight deviations from this strict definition according to the Federal Register of Buildings and Housing (RegBL) due to data storage by data suppliers and what is customary in the industry. The IMPI mainly makes allocations based on the structure of the building, not its use (e.g. as a prayer room). The IMPI also counts the following operties as single-family houses:
- - Single-family houses with an ancillary dwelling
- - Single-family houses with commercial premises - if the proportion of living space - measured in terms of area - is larger.
- - A rare case is the 2 to 3 family house in which the owner lives themselves.
