If the height of the ceiling allows it to be slightly reduced, you can do this: put the lags on the litter of cork material, and fill the cavity between them with mineral wool stitches, and then eliminate the gap with a layer of rough plywood. If the height from the ceiling is low and is, for example, 2, 5 m, it is better to resort to the help of cork material, panels 20 mm thick, which are laid on the floor in front of the screed itself. Before performing a screed with a cement mortar on a stacked sound insulation, place a cork strip around the perimeter of the room and observe the thickness of the screed, as a result of which the walls of the house will not come in contact with the floor plane, and in turn, the stream of noise waves will decrease. From all of the above, it becomes clear that the sound insulation of the floor is not difficult and it can be done independently. This could be said and “enough”, but many experienced craftsmen explain that if you perform litter from cork panels directly under the laminate, linoleum, carpet, then the noise will completely decrease. If your budget allows you to supplement the repair with this material, do not hesitate, it will not be worse.