The Riverside County Administrative Center in Riverside, Calif., built in 1967, houses the offices of various county departments and the county board of supervisors. The basement of the 185,000 ft² (17 209 m²), 13-story structure also houses the county's emergency operating center, with its own backup HVAC system. The building's 30-year-old HVAC system had a high energy cost and required considerable maintenance. In addition, the client desired improved indoor air quality.