In a condominium, a distinction is made between the common portions and the private portions.
The common portions belong to the syndicate of co-owners, while the private portions are the property of a co-owner.
The law provides that the common portions are the parts of the buildings and grounds assigned to the use or utility of all the co-owners or several of them. Thus, generally, the structure, the access roads, the premises used by all, the elevators, the corridors... are common parts.
The condominium bylaws may however contain a different distribution. For example
The private parts are the parts of the buildings and grounds reserved for the exclusive use of a specific co-owner. They are the exclusive property of each co-owner. The condominium regulations describe them in detail. It is thus the apartment of each co-owner.
Note: the condominium regulations, if properly drafted, make it possible to determine whether a part of the building is a private or common area.