A dwelling is considered to be permanently occupied, if on or more inhabitants are registered for permanent residence in the dwelling.

A family house is a building intended primarily for family living with a separate entrance from a public road that has a maximum of three dwellings, two above-ground floors, and an attic.

A residential building (according to the Building Act) is a building intended for living that consists of four or more dwellings with a common main entrance from a public road.

The number of permanently occupied dwellings with bathrooms, while the bathroom is a separate room in the dwelling with a bathtub or shower. A dwelling with a bathroom also means a dwelling that has a shower located in another room.

The number of permanently occupied dwellings with a gas connection defines whether the dwellings have established a gas connection to the public network. The use of propane-butane bottles and propane-butane tanks is not considered a gas connection.

Number of permanently occupied dwellings that use central, single or individual-storey heating system as the type of dwelling heating.