Abstract: A roof construction for use upon a deck or pre-existing roof which includes a series of elongated coplanar roof panels assembled edge-to-edge at their ends in a line and top-to-bottom at right angles thereto juxtaposed over said roof or deck. Each roof panel comprises a thin metallic skin having a rectangular top plate with a downturned front edge along its length. Below the front edge is an assembly slot bounded by an outturned anchor plate adapted for securing to said roof. A series of snap lock stops are formed in said panel and extend into said assembly slot. The top plate has a downturned rear edge which terminates in a flexible outturned assembly plate spaced from and projecting rearwardly of the top plate. The assembly plate terminates in a reverse-turned snap lock flange which extends above said assembly plate.