IMEG provided structural engineering design services for the San Francisco Day School building expansion and renovation located at 350 Masonic Avenue in the Lone Mountain neighborhood in San Francisco. The project consists of a new 22,500-sf, four-story building expansion of the current independent school campus building that serves approximately 400 students from K-8 Grade. The building addition features classrooms, basement and a roof deck community use space. Adjacent to this new structure addition is an existing 3,000-sf building that was renovated. The structure is a traditional steel-frame building with buckling restrained braced frames and steel special moment frames as lateral force resisting system. Notable features include the grass covered field on the roof and the two-story ballroom.