The Physical Science Building contains 179 assigned spaces and 74,227-SF which include teaching, research and self-instruction laboratories; lecture, storage, support, museum and gallery spaces; faculty and administrative offices, and conference rooms. Our team was awarded this Collaborative Design-Build project to transform this conglomerate of existing two- and three-story concrete structures into a flexible learning environment with the swing space needed for the future expansion of the main campus. The third level of the 1969 addition is the most problematic component of the Physical Science Building. The roof framing and the pre-cast cladding system are both seriously overstressed because the exterior envelope system on the third level is partially cantilevered over the roof of the original 1960 Building. This has manifested in tensile cracking of the pre-cast system and substantial moisture penetration of the exterior skin. We are utilizing 100 percent of the existing structure’s capacity to reduce cost and schedule. Our complete solution supplements the existing structural systems to allow us to meet the minimum requirements of the CSU Seismic Provisions while minimizing the extent of additions to the structure.