100giants#5

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HDR‘s cost-conscious, eco-minded project, located on a former industrial site, is the first mass-timber, net zero–energy building for a public utility in Southern California. Linked via a pedestrian skybridge to the wastewater-treatment plant across the street, the 109,000-square-foot, three-story Orange County Sanitation District Headquarters in Fountain Valley serves as both workplace and community destination, with immersive exhibits educating visitors, tour groups, and field-tripping schoolkids. (Because of the potential adolescent-joke nature of the plant’s function, humor is incorporated into the storytelling signage.) The double-height lobby flaunts a mass-timber diagrid structure—its layout inspired by the sanitation plant’s anaerobic digester—that pairs with a wood-slat ceiling providing acoustic dampening and integrated lighting. The office proper emphasizes collaboration and wellness, with abundant daylighting, easy-access common spaces, and enticing terraces and interior courtyards with native plantings. Numerous features helped put the all-electric building on track to achieve LEED Gold status. The timber was shipped by train from Oregon when needed to reduce carbon footprint and avoid storage costs. Passive solar shading and the building’s orientation maximize daylight while reducing heat gain. Interiors are 90 percent Red List–free. And much of the on-site energy needs are met with biofuel—captured as a waste product from sewage processing.