Cadastral operation which consists in determining its relative position on a cadastral plan, indicating its boundaries, measurements and area and assigning a number to it. No declaration of co-ownership may be registered unless the immovable is the subject of a cadastral plan that contains the immatriculation of the private and common portions. In addition, the Civil Code of Quebec specifies that immatriculation of the private and common portions of a vertical divided co-ownership may not take place before the foundation and main walls of the building in which they are situated allow measurement of their limits.