A set of operations or activities aimed at preserving the common portions for restricted use of the immovable in good condition and preventing their deterioration. The syndicate of co-owners has, in principle, the obligation to ensure the preservation of the immovable and, thereby, the maintenance of all types of common portions. However, the declaration of co-ownership may provide that the maintenance of common portions for restricted use, such as balconies, be entrusted (in part) to the co-owners who have the enjoyment.