In many apartments (mainly in new buildings), the floor slabs are laid quite evenly, and their joints are reliably sealed; as a rule, a cement-sand screed is installed on top.
However, defects may remain. The method of elimination depends on their nature, as well as on the type of flooring chosen.
Local mortar drips on the screed from the developer can be cut off with a chisel, and small holes and traces of the rule can be removed with a cement-polymer or polymer putty for concrete, thus obtaining a ready base for laying tiles, laminate or parquet boards. It is not advisable to lay rolled coverings directly on the rough screed, since the slightest defects appear on them (finishing leveling with a self-leveling mixture is necessary). If solid boards, glued parquet boards or block parquet are chosen as a covering, it is necessary to ensure high tear strength of the putty. Two-component epoxy putty is perfect for this purpose, but it requires careful preparation of the base – dust removal, degreasing, and sometimes primer with a strengthening primer.