Abstract:
A roofing system and method of securing insulation board to a roof deck free of mechanical fasteners includes the deck, a plurality of the insulation boards, and a flexible waterproof membrane which covers the boards. First and second embodiments of the invention include flexible polyisobutylene pads and strips respectively, which have opposite top and bottom pressure sensitive adhesive surfaces. A plurality of the pads are adhered to the insulation boards by their adhesive top surface at locations where mechanical fasteners otherwise would be necessary to secure the boards to the roof deck. A pair of the strips are adhered to the boards by their adhesive top surface at spaced locations. After removal of a release sheet from the bottom surface of the pads or strips, the boards are placed and pressed on the roof deck, and the exposed adhesive secures the boards to the deck free of mechanical fasteners. A flexible waterproof membrane then is placed over the insulation boards and is either mechanically fastened to the roof deck independent of the insulation boards, or is adhesively attached to the boards.