A foundation floor system and associated transport apparatus for use in combination with a transport vehicle and an on-site foundation includes a frame, the frame including opposing I-beams each having an upper flange; a plurality of bar joists each extending perpendicularly between the opposing I-beams; each of the plurality of bar joists being in parallel alignment relative to each other and having first and second ends secured to corresponding ones of the opposing I-beams; first and second tube beams each being located interiorly adjacent to a respective one of the opposing I-beams beneath the upper flange, each of the first and second tube beams surrounding an end channel; and wherein the frame forms a surface that is sized and configured for receipt of a building structure; and a transport apparatus that is configured for transporting the frame thereon, and the transport apparatus including a tongue adapter and an axle adapter.