Abstract: Disclosed is a shutter system and its panels in which at least one panel is formed of corrugations, and in which the subject panel is perforated. Ideally, the perforation is employed in a panel having an isosceles trapezoidal rib, with the perforations running the full length of the face of the rib. The adjacent panels are secured by a wide variety of means often implying a keyhole slot at the top and the bottom of each panel to engage a fastening means which is secured to the structure being covered. Different mountings including direct mountings, of course, are contemplated. The panels, whether perforated or not, are formed from essentially the same material and as a consequence thermal expansion and contraction between adjacent panels is accommodated by the mutual expansion and contraction of each, thereby requiring only accommodation of the shutter system with regard to the opening in the dwelling which it closes.