A reinforcement for flexible film (10) for sheets for covering agricultural or industrial or similar areas, the reinforcement consisting of reinforcing bands formed by means of hot extrusion and provided with holes (12) for the anchoring cords to pass through, said reinforcement comprising at least one ribbing (13) made from the same material as the reinforcement and applied also by means of hot extrusion, being indispensable for the anchoring of the covering sheets.
