Plastic/metal composite stress plate and method of using same for securing a thermoplastic roof membrane to roof deck

摘要

A two-piece fastener assembly for securing thermoplastic roof membranes to an underlying roof deck having: a stress plate and a fastener. The stress plate consists of a pre-fabricated metal layer and a thermoplastic layer which are integral with each other. The stress plate has top having three flat surfaces and two circumferential portions, forming ridges or protuberances connecting the flat surfaces. In a method aspect the steps of securing thermoplastic roof membranes to an underlying roof deck, includes: placing a first thermoplastic roof membrane on the roof deck; placing a line of stress plates on the marginal portion of the first thermoplastic roof membrane and securing the stress plates along with the first thermoplastic roof membrane to the roof deck by use of the fastener; placing a second thermoplastic roof membrane to overlap the line of stress plates and the marginal portion of the first thermoplastic roof membrane; and applying heat and pressure to the line of stress plates and the overlapped portion of the first and second thermoplastic roof membranes to fuse them together and provide a waterproof covering over the roof deck.