Prefabricated waterproofing membrane, composed of a special compound based on modified bitumen with a new generation of elastomeric polymers (BPE), reinforced with a woven non woven fiberglass mat. The upper surface is self protected with a laminated aluminum (LAM-AL) or copper sheet (LAM-CU). The self protection with a metal laminated sheet, besides providing aesthetic characteristics to the product, protects the membrane from atmospheric agents and allow a sufficient reflection of the sun rays, increasing the durability. To allow for a proper bond between the sheets, the protected is supplied with a side selvedge.