Atlanta-based Atlas Roofing Corp.’s ACFoam Composite consists of Atlas closed-cell polyiso bonded to 1/2-inch perlite with a fiber reinforced felt facer. The perlite top eliminates the need for cover boards or vented base sheets normally recommended over foam insulations. ACFoam Composite may be used with BUR, modified bitumen, and mechanically attached and loose-laid ballasted single-ply systems.