NOVELTY - A lightweight, durable exterior roof tile comprises a composition (C1) comprising polymeric isocyanate element A and composite 1,1,1,3,3-pentafluoropropane (HCFC-245fa) blown element B.    USE - As lightweight, durable exterior roof tile (claimed), useful to cover plywood and tarpaper.    ADVANTAGE - The roof tile is an improved building roof tile that is featherweight, hurricane proof, yields a high R-value for insulation, offers low thermal transference into attic space, is able to be retrofitted to any sloped roof without structural build-up, is molded into single or triple sized units, can produce solar energy, is easy to transport and install, cannot break under foot or when extreme pressures are applied and can be molded to look like slate, wood, flat or roll tile.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a roof comprising either: a substrate and an array of molded tiles of different functional shapes including field tiles, starter tiles and roof peak and edge tiles, where all of the tiles molded from the composition (C1), the field tiles and the starter tiles have flat bottom surfaces including recessed areas with grooves for receiving poly adhesives; poly adhesives applied to the recessed areas of the field tiles and the starter tiles, where the field tiles and the starter tiles attached to the substrate by the poly adhesive; or roof tiles joined side-by-side and in a top to bottom array in rows covering a roof substrate and attached to the roof substrate with a poly adhesive; and a wiring harness connecting all of the solar modules mounted in the roof tiles electrically for generating electricity; or molded roof tiles constructed from a polyurethane material, where each of the tiles includes a flat bottom surface having a recessed areas that includes the grooves; poly adhesive foam applied to each of the molded roof tiles recessed areas; a roof substrate; molded roof tiles attached to the roof substrate with the poly adhesive foam applied to each of the molded roof tiles recessed areas.