Protected membrane roof system for high traffic roof areas

Abstract From the Canadian patent

An insulated roofing system is provided in which a waterproof membrane is applied to the roof deck. Extruded panels of closed cell polystyrene foam are provided on top of the membrane, thus protecting the membrane from thermal cycling, ultraviolet rays and physical damage. The foam panels provide excellent insulation and are resistant to water. A waterproof plastic film is bonded to the undersurface of each panel positively to exclude water. The foam panels are cut mechanically or are grooved to provide on the upper surface integral ribs spaced by channels. Concrete panels are said directly on top of the polystyrene foam and rest gravitationally on the ribs. The ribs provide for ventilation …