Abstract: A composite roofing system in which a layer of polystyrene or polyurethane foam insulation board is encased in layers of lightweight insulating concrete and the surface of the foam insulation board is roughened to strengthen the interfacial bond with the surrounding layers of concrete and provide increased resistance to wind uplift, seismic activity, and degradation of the roofing system caused by vertical loads. Moisture which might otherwise become entrapped in the roofing system by the impermeable insulation board is ventilated out of the system by a combination of openings through the insulation board which permit the migration of moisture between the layers of concrete, and a plurality of lateral slots cut in the insulation board to permit further migration of moisture out of the system.

Abstract: A fastener for securing built-up roofing membranes used to waterproof cementitious roof decks combines the conventional nail used for this purpose having a head and a shank portion designed to resist withdrawal of the fastener from the deck, with a non-integral tab penetrated by the shank of the nail and of larger diameter than the nail head, the tab having a design which allows the fluid asphalt conventionally poured over the nail during construction of the roofing membrane to bond the portion of the membrane beneath the tab and thereby increase the wind uplift resistance of the covering material. Removability of the tab allows its detachment in applications where increased uplift resistance is unnecessary.

Abstract: A sheet metal nail of the type for securing built-up roofing membranes used to waterproof cementitious roof decks has a head and a hollow shank portion integral therewith and designed to resist withdrawal of the nail from the deck in a conventional manner, the head however being of larger diameter than the head of the conventional nail used for this purpose and further having a design which allows the fluid asphalt conventionally poured over the nail during construction of the roofing membrane to bond the portion of the membrane beneath the head and thereby increase the wind uplift resistance of the roofing membrane. The nail is preferably of "one piece" construction formed from a sheet metal blank.

Abstract: A fastener for securing built-up roofing membranes used to waterproof cementitious roof decks combines the conventional nail used for this purpose having a head and a shank portion designed to resist withdrawal of the fastener from the deck, with a non-integral tab penetrated by the shank of the nail and of larger diameter than the nail head, the tab having a design which allows the fluid asphalt conventionally poured over the nail during construction of the roofing membrane to bond the portion of the membrane beneath the tab and thereby increase the wind uplift resistance of the covering material. Removability of the tab allows its detachment in applications where increased uplift resistance is unnecessary.

Abstract: Improved lightweight insulating concretes containing expanded vermiculite or perlite aggregate and of the type which are mixed and pumped to roofs of buildings and the like are described. The improved concretes are mixtures in specified proportion of cementitious binder such as Portland cement, expanded vermiculite or perlite, air-entraining agent, polyelectrolytic sulfonate dispersing agent and preferably an inert densifying particulate, which, can be cast as thin cross-section, high strength layers requiring low amounts of "in-place" water, without sacrificing necessary properties such as yield, pumpability, etc. The improved concretes are preferably used as layers over plastic foam insulation boards in the formation of sloped or non-sloped insulated roof systems constructed at the job-site.