NOVELTY - The roof covering system comprises a flexible sealed bituminous membrane (1) positioned as contiguous strip at the edge and fixed on a sub-adjacent support, and sections (3), bars and a cross-sectional piece fixed at regular intervals on the membrane to form a rigid assembly. The sealed membrane comprises semiconductor photovoltaic cells on its outer side in the form of a monojunction or heterojunction thin film. The sections are covered on exposed surface after fixation. The membrane is a synthetic membrane, and comprises a woven reinforcement or a backing layer for reinforcement.    USE - The roof covering system is useful in industrial-, residential- and office buildings.    ADVANTAGE - The roof covering system provides excellent sealing function, can be easily and economically fabricated, and avoids the mechanical constraints in the buildings using photovoltaic materials.    DETAILED DESCRIPTION - The roof covering system comprises a flexible sealed bituminous membrane (1) positioned as contiguous strip at the edge and fixed on a sub-adjacent support, and sections (3), bars and a cross-sectional piece fixed at regular intervals on the membrane to form a rigid assembly. The sealed membrane comprises semiconductor photovoltaic cells on its outer side in the form of a monojunction or heterojunction thin film. The sections are covered on exposed surface after fixation. The membrane is a synthetic membrane, and comprises a woven reinforcement or a backing layer for reinforcement or improving adhesion. The bituminous membrane comprises a reinforcement in the form of a glass plate, polyester and aluminum sheet. The sealed membrane comprises plasticizer, pigments, biocides, flame retardants, UV absorbers and antioxidants. The thin film is produced on the membrane by projection under vacuum or impression using an ink roller containing semiconductor nanoparticles. An underlying support is arranged on which the covered membrane is fixed. The underlying support is an insulant, a concrete base, a sheet or a metal pan, a waterproofing membrane, a wood structure (4), a wood panel (5) or a wood sheathing. The covered membrane of the cell is separated from the underlying support by an interposition geotextile. The underlying support is equipped with a unit for ventilation of the photovoltaic cells. The thin film is covered with a protection layer close to atmospheric weather. The sections are mechanically fixed to the membrane by adhesion, cold welding or hot air welding. Each section is single piece formed by a transverse flange and a projecting web mounted with a cross section of triangular shape, square, round, cylindrical or sagging.    DESCRIPTION OF DRAWING(S) - The figure shows a cross-sectional view of a roof covering system.    Sealing membrane (1)    Steel bag (2A)    Vapor barrier (2B)    Sections (3)    Wood structure (4)    Wood panel. (5)