San Francisco, CA

5M, 415 Natoma Street


5M at 415 Natoma Street is a twenty-five-story, mixed-used high rise in San Francisco’s SOMA neighborhood. With condominiums, apartments, community green space, and Class-A office space, the development provides much needed additional residential capacity in the city. The building features large cantilevers in the lower floors that support multiple terraces and provide an inviting aesthetic for the public spaces, retail, and restaurants at street level. SGH provided construction engineering services to the steel fabricator/erector.

We helped the construction team implement their preferred sequence for the 6,000-ton steel structure. Highlights of our work include:

  • Evaluating the partially constructed building behavior under lateral loading
  • Designing shoring and bracing, including a temporary lateral-load-resisting system that stabilizes the structure during erection and providing bracing options to the structural steel erector to facilitate erection of more than eight levels of steel above the highest completed floor system
  • Analyzing the building stability during construction to facilitate the placement of the concrete slabs on metal deck for the elevated floors that were constructed several levels above the lowest level of erected steel
  • Designing a temporary lateral-load-resisting system to stabilize the structure during placement of the concrete slabs, including evaluating multiple levels of floor framing and detailing modifications for the steel beam connections to transfer lateral forces
  • Designing temporary support for large, cantilevered balconies and terraces
  • Providing erection requirements to maintain lateral stability of deep, long-span transfer plate girders during erection of the columns that are supported by the girders
  • Designing weld platforms, including temporary connection details
  • Designing temporary bracing for tower crane tie-ins constructed between floors to facilitate crane jumping
  • Evaluating column lifting lugs and base for temporary construction loading
  • Assisting with the erection aid design

Project Summary



Completion Date


Project Size
New Construction
Residential | Mixed-Use
Schuff Steel | Swinerton Builders
Specialized Capabilities
Temporary Construction

Key team members

Keith Palmer
Keith Palmer
Associate Principal
Kevin Moore
Kevin Moore
Structural Engineering Region Head, West