Abstract: The modular building is a basically circular building structure formed by assembling pie or wedge shaped modular elements. The modular elements are radially attached around a center column anchored in a column footing. The attachment of the modular elements is by use of collars on the center column which allow rotation about the floor collar and slotted motion about the roof collar. The modular elements are not rigidly attached one to the other. This allows for limited independent movement relative to each other such as during earth movement. The floor sections of the modular elements are mounted on foundation elements assembled radially around the center column. Use of modular elements allows factory manufacture and assembly efficiency and then construction of the modular building at the building site.