Abstract: Disclosed is a roof structure containing a fire retardant. The roof structure has a fluted deck with troughs therein and a meltable insulation layer overlying the fluted deck. The fire retardant includes a series of non-flammable absorbent strips or strip segments which can be placed in the troughs of the fluted deck for retarding the flow of molten insulation in the trough during a fire by absorbing the molten insulation material in the trough.

Abstract: 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 laid directly on top of the polystyrene foam and rest gravitationally on the ribs. The ribs provide for ventilation and moisture removal on hot, dry days. Removal of water vapor is enhanced by the increased area exposed to the ambient environment and derived from the cratered surfaces generated by cutting sections out of the foamed plastic panels.

Abstract: An insulated roofing system is provided in which a waterproof membrane is applied to the roof deck. Extruded panels of closed cell polystryrene 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 under surface of each panel positively to exclude water. The foam panels are extruded and are provided on the upper surface with integral ribs spaced by grooves. Concrete panels are laid directly on top of the polystyrene foam and lie gravitationally on the ribs. The ribs provided for ventilation and moisture removal on hot, dry days.