Polycarbonate roof panel having reinforcement recess for coupling to sandwich panel

A modular panel system, comprising:

• at least first and second mutually juxtaposed panels, each of said panels being supported by spaced apart purlins of a building structure that extend along a width of the panels,
• the second panel having a projection projecting upwardly from an upper surface of the panel and extending along a length of the panel at a first side of the panel constituting a proximal side of the projection,
• said projection having on a distal side an undercut defining an internal recess extending along a length of the panel, said undercut having a lower surface flush with an upper surface of the panel,
• the first panel having an integral wing-type female coupler of complementary shape to the projection, said female coupler extending along a length of the first panel and overlaying the projection of the second panel, and
• fasteners of similar shape to the wing-type female coupler for overlaying the wing-type female coupler, each fastener having a hook shaped lip along an edge thereof for engaging the undercut of the projection and being fixedly attached using a bolt that extends through the fastener, the wing-type female coupler and the projection, whereby the second panel is supported between the wing-type female coupler of the first panel and the hook shaped lip.