Prefabricated modified composite waterproof membrane with differentiated waterproofing compounds. The upper face waterproofing compound is composed of distilled bitumen and elasto plastic polyolefin’s with high heat resistance and cold flexibility, while the lower face compound is composed of distilled bitumen and special polymers which give incomparable characteristics of adhesion to old membranes with mineral self-protection. The PLURA R G200 membrane is finished on the upper face with a special white mineral with good reflective capacities, besides extending the life expectancy of the membrane, its reduces heat buildup both on the external surface as well as inside the building with a reasonable savings in terms of energy consumption. The emissivity of the PLURA R G200 furthermore favors the dissipation of accumulated heat during the night.