Process for insulating and sealing essentially flat roofing and coating used in this process

Process for insulating and sealing a roofing that forms an essentially flat substrate, such as a concrete terrace roofing, characterized in that it essentially consists of:

• Coating said substrate (2) with a liquid or viscous composition (3) by covering rough spots (4) and by filling hollows or emergent cavities (4′) that are present on the surface of said substrate (2),
• Applying said insulating layer (1) or individual elements that are intended to form said insulating layer (1) on the coated surface of said substrate (2) before the previously applied coating layer (3) solidifies, whereby said coating layer (3) forms, after drying or polymerization, a water-vapor barrier and an agent for adhesion of insulating layer (1) to said attachment substrate (2), and, finally,
• Applying to insulating layer (1) a sealing coating (6) that comprises at least one layer of bituminous or synthetic or analogous membranes.