Photo courtesy of Tetra Tech King County’s new South Plant office and laboratory building has many energy-efficient features, including solar panels, high-efficiency lighting and glazing, and low-flow water fixtures.

When King County decided to replace its South Plant regional administration and laboratory facilities in Renton, it wanted a structure that was functional and environmentally friendly.

The new building, which includes a 3,500-square-foot laboratory and 21,000 square feet of office space, fits in a modest footprint designed for energy savings and employee comfort and productivity. Tetra Tech was the lead architect and engineer.

Highlights include natural lighting in more than 83 percent of the spaces. Integrated daylight and occupancy sensors reduce lighting energy use. Reclaimed water from the adjacent treatment plant was used in the restrooms, helping to reduce water use by 76 percent.

Because the structure was built on the site of the existing facilities, 20- to 30-foot-deep site fill was reused, reducing costs and avoiding the need for piles for new construction. Cabinets, masonry and countertops from the old buildings were also reused.

A 1,000-square-foot black solar panel integrated into the south wall will provide approximately 15 percent of the building’s heating energy. Other measures, including extra insulation, extensive building energy modeling, variable-speed drive hydronic pumps and fans, high-efficiency lighting and glazing and exterior sunshades will optimize building performance and energy conservation.