County of San Mateo, County Office building 3 (COB3)
Redwood City, California
Excellence in sustainability
Region: Hell California
Sent by: Construction of Trubeck
Owner: San Mateo County
Lead design company and structural engineer: Skidmore, Owings & Merrill (Som)
General contractor: Construction of Trubeck
Civil Engineer: Inc.
Subcontractors: Mechanical Critchfield; JW MCCLENAHAN; CSI electrical contractors; Cosco fire protection; Architectural and aluminum glass; Western wood structures
The sustainability was more in the head for the county officials and their project team working in this $ 195 million massive wood office building. The five-story building with 208,000 square meters is the first Massive Mass Wooden Civic building, designed by Net-Zero Platinum built in the United States, has a massive wood and a glulam frame with a cross-lined wooden roof structure, which helped achieve a reduction of 85% in carbon embodied in comparison with a conventional structure.
“San Mateo County aimed to create a daring civic building with strong sustainability goals,” said Mark While, Trubeck Construction Executive Project in a statement.
Reid Schultz/Truebeck Construction photo
Trubeck sought companies that could install the massive wooden package and blocked at three -phase material prices. This saved more than $ 1 million on material costs. The design allowed additional savings by using CLT of five layers instead of seven layers, complementing Douglas Fir on the upper and lower layers exposed with low cost wood for the center.
Rowan Jack photo
The whole electric building has 333 kW of solar matrices in situ. MEP systems were designed for efficiency and have a redundancy providing greater resilience and future flexibility. The building has 190 automated operating windows that provide natural ventilation and passive cooling every night when the outer conditions are soft.
The massive wooden building has a high performance envelope, solar design strategies and passive in place.
Rowan Jack photo
To minimize heat gain and reduce the need for artificial cooling while optimizing the day’s light, the outer glass of the north facades is embroidered and shaded, while the glass on the east and west facades is protected by the fins. The site also has bioretence planters that absorb and treat the entire rainwater runoff of the site. Compared to other buildings of this size, COB3 uses about 610 MW less power and 250,000 less gallons of water a year. “This is not only the greenest civic building in the United States, but one of the most aesthetically pleasant,” said David Canepa, President of the San Mateo County County Supervisors in a statement.
