Abstract: A building is constructed by utilizing pre-fabricated elements with the load carrying and supporting sections being constructed of hat-shaped sections generally U-shaped in cross section. A plurality of these hat-shaped sections having at least one upwardly extending flange are secured around a floor member so that the flanges extend vertically from the floor. A series of other hat-shaped sections are then secured to the vertically extending flanges, at their basis and disposed peripherally in spaced parallel relation extending upwardly from the floor. Wall panels are then secured between adjacent vertical hat-shaped sections and additional hat-shaped sections constituting wall plates are placed on top of the wall panels and vertically extending hat-shaped sections. A series of tie-beams are then disposed on top of the wall plates adjacent opposing vertically extending hat-shaped sections.