Residential Roof Step Flashing Roll Forming Machine, Asphalt Shingle Roof Step Flashing Equipment This Step Flashing Roll Forming Machine is specially designed to produce L-shaped overlapping step flashing, which is the critical waterproof flashing component for North American roofing systems. Step flashing is installed at roof-to-wall junctions, chimney sides, dormer walls and roof penetration areas. Each piece overlaps like shingles, diverting rainwater and melting snow