US Patent 8240095 Deck assembly with liner panel

A deck system is made by joining deck units, each having a hat-shaped profile fastened to the topside of a profiled bottom panel. The bottom panel has nestable or interlocking side laps and one or more “dove-tail” shaped recesses formed therein. These recesses, which may be concave upward or downward, give the deck unit additional strength as a defined, confined location for use to run conduit and to provide vertical support for vertical loads. The deck system may be combined with a layer of concrete for use as a floor or roof.