County Executive’s Office

County Office Building 3 or COB3 is the new cutting-edge home for San Mateo County employees and is located in the heart of historic Redwood City. The nearly 208,000 square foot building is constructed of Mass Timber featuring wood columns, beams, and Cross Laminated Timber (CLT) floor decks. The County is proud to construct the first Civic Building in the Country that boasts CLT construction and Net-Zero energy design. The timber frame criterion was selected for structural and environmental benefits as wood dramatically lowers the building's carbon footprint by reducing the reliance on structural steel and concrete. The inherent lightweight nature of wood framing also allows reduction of foundation sizes and most importantly a structure that performs exceptionally well when subjected to lateral seismic loads. There are also 4 main traditional steel cores in the building which house 5 elevators, egress stairs, and provide the bulk of the lateral stability for the structure.

As an unwavering reflection of the County’s commitment to sustainability and leading by example, the building will also be designed to be "Net Zero" energy. This means that the COB3 facility, which is designed to house 600+ employees, will produce 100% of the energy to keep the building functioning and operational. The energy production comes from numerous arrays of PV panels located on the roof of COB3 and on the adjacent parking garage. Producing your own energy is only half of the equation and the County has doubled down to ensure that the mechanical and overall performance of the building is world class and incorporates automated roller shades and windows that increase the overall energy efficiency. With all the cutting-edge industry and design efficiency standards used on the project, the goal is to achieve LEED Platinum Certification.

Project Details- COB3 PDF