If the warm -up vapor barrier film is completely absent on the insulated roof, then it is precisely in the cold season that the temperature difference in the room and on the street under the roof arises, steam will constantly form. Steam will constantly moisturize the insulation. Not even a greatly significant moisture of insulation can ultimately lead to very significant losses of all thermal insulation properties. Removal from the surface of the entire heat -insulating layer and can only be ensured by ventilation. In order to prevent all heat to be eliminated along with moisture, they use windproof patterns that need to be covered with insulation. It is most important to use precisely windproof films that need to be covered with insulation. It is most important to use precisely windproof films, if the insulation is glass wool, because without its additional protection, all the winds of the wind will blow out its particles.