Project Description / OverviewNYA provided structural engineering services for the seismic upgrade and modernization of the historic 50 United Nations Plaza building in San Francisco, CA. This 1936 Beaux-Art style building which is on the National Register for Historic Places, provides approximately 193,000 sq. ft. of office space and cutting edge workspaces for various General Administration departments.
The seismic upgrade of this 6-story steel frame and unreinforced brick masonry infill building consists of the addition of new concrete shear walls in select and unobtrusive locations throughout the building. Improvements also include stabilization of hollow clay tile partitions along the historic sensitive corridors and bracing of parapets.
When NYA began involvement on this project at the 50% Construction Documents phase, the structural systems were 50% over budget, based on a proper design scheme. NYA quickly developed a very efficient seismic retrofit system that brought the structural costs down below the original budget and allowed the project to proceed. The completed project provides a high performance green building with a LEED Gold rating.