Abstract: A roof structure includes a lightweight insulating concrete layer, a waterproof membrane overlying the concrete layer, and a plurality of adhesive pellets that are at least partially embedded in the concrete layer. At least some of the adhesive pellets are in contact with an adhesive layer of the waterproof membrane so that the waterproof membrane and the concrete layer are both adhesively bonded together.

Abstract: A lightweight insulating concrete composition includes a cementitious forming material and a lightweight aggregate combination of expanded vermiculite and expanded perlite, the weight ratio of one to the other not exceeding about 2:1. Preferably, the composition is about 4 parts by weight cementitious forming material and about 1 part by weight lightweight aggregate. The cementitious forming material may be a hydraulic binder and accelerator combination, and may be Portland cement, plaster of Paris, and terra alba, in a weight ratio of about 5:4:1, or calcium aluminate cement, and plaster of Paris, in a weight ratio of about 11:5. The composition may further include an air entraining admixture in an amount between about 0.5 and about 2.0 percent of the total weight of the mixture, where neutralized vinsol resin and alpha olefin sulfonate are acceptable, and a surfactant in an amount between about 0.3 and about 1.

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: The invention relates to a gypsum-based cementitious composition capable of upon mixing with fine aggregate in a weight ratio to said gypsum-based cementitious composition of from about 1.25:1 to 2.5:1; and sufficient water to provide a pumpable, self-leveling wet gypsum-based cementitious composition having a flowability such that the wet gypsum-based cementitious composition completely self-levels to produce a topographically smooth surface without floating or finishing, providing, upon hardening, a sub-floor resistant to delamination from its substrate having a dust-free surface and compressive strength in the range of about 2500 to 6000 psi. The invention further relates to methods for making floor underlayments using these compositions, and for making the compositions.