Alten Construction worked with DLM Architecture, Kitchell and San Francisco Unified School District to seismically retrofit and renovate three existing concrete buildings in nine phases stretching over two-and-a-half years within an occupied high school campus. As part of the seismic retrofit, Alten Construction drilled forty piers into existing bedrock and placed integral concrete grade beams; shotcreted shearwalls three-stories high in two different phases; installed fiber reinforced polymers (FRP) for concrete strengthening at seventy-two exterior columns at three floors, and placed FRP diaphragm strengthening at the existing concrete roof deck; and installed four steel brace frames.
For the renovation, Alten Construction demolished and framed new walls as required for new administration offices and restrooms. We updated the existing library with new ceilings, skylights and light fixtures. At the existing auditorium, we extended the stage and placed new maple flooring as well as a new chair lift; we also replaced the ceiling and light fixtures. In the classrooms, we placed new ceilings, light fixtures, flooring and cabinetry. Throughout all three buildings, we painted all of the interiors and exteriors; we replaced all three roofs; and we replaced all of the existing windows and installed new storefront systems. We also upgraded the existing elevator, and we updated the existing fire sprinkler, fire alarm, security, lighting control and mechanical systems. The sitework included a new emergency generator, site lighting, underground utilities, irrigation, landscaping, concrete flatwork and seat disks, concrete retaining walls up to ten-feet high and asphalt paving.