MAC House is the creation of new academic housing to be located within the riverside area in Harvard’s campus. The housing is in the form of a separate 13th house. The new 13th house includes both housing and an academic, cultural, social and athletic component. The new house is located on the top of the existing gym facility ‘M.A.C. (Malkin Athletic Center),’ becoming not only a house but also a student center by interlocking with the athletic facility. The new house is transformed from traditional courtyard housing typology. The enclosed courtyard transforms to a horizontal and vertical courtyard. Transformed mass interlocks with the existing athletic facility vertically, horizontally, functionally, and visually. Units are aggregated for mixing social activities. Traditional housing only has horizontal social interaction between roommates and students who are living on same floor. However, the proposed aggregation system creates mixed social relationships. Students can participate vertical and horizontal social activities. In addition, the multiple courtyard system helps diversify social interactions.