Abstract: A membrane roof system includes a single ply water impermeable membrane held to a roof deck by two separate fastening systems. The peripheral portion of the membrane is bonded to the peripheral edge of the roof deck by an adhesive and without mechanical fasteners. The central portion of the roof membrane is held down by traditional fastening means such as ballast, membrane-penetrating mechanical fastenings or preferably, non-membrane-penetrating mechanical fasteners. This provides maximum adherence around the periphery to withstand high uplift forces at a relatively low cost.