A manufactured building system has a pair of pre-stressed multi-stemmed concrete floors. The pre-stressed multi-stemmed concrete floors are adapted to contact each other on one parallel side edge to form peripheral edges and a central joining edge. A part of a building is coupled to a pre-stressed multi-stemmed concrete floor. Also described is a Method of Transporting the pre-stressed multi-stemmed concrete floors with the partial building coupled there to, to a site. Also described is a Method of Manufacturing a pre-stressed multi-stemmed concrete floor.