Protectobase 180 Specialty Cover Board is a composite of IKO Protectoboard, a mineral fortified asphalt core board that is factory laminated to an SBS modified bitumen base sheet. The base sheet is constructed with a tough non-woven reinforced polyester mat strengthened with select glass fiber strands. The bottom surface of the product features the Protectoboard finish and the top surface has a light micro-perforated film which permits heat fusing to an IKO SBS modified bitumen cap sheet. The base sheet of Protectobase 180 includes a dual selvage self-adhering SBS side lap that is staggered from the product to allow easy joining of the base to adjacent Protectobase 180 boards. This allows for a quick application of a roofing system’s base layer. The high compressive strength of the Protectoboard along with the factory application of the base sheet ensures a fast and reliable method of installing the overlay board and the waterproofing base layer in one easy step.