The Rookery

HVAC and Electrical System Studies

HVAC and Electrical System Studies - Chicago, IL


The Rookery is a 280,000-square-foot office building in downtown Chicago, constructed in 1887-88. The building is both a Chicago Landmark and a National Historic Landmark. G/BA provided HVAC and electrical system studies and recommendations to improve efficiency.


Work at The Rookery, a historic property designed by Burnham and Root, included evaluation of HVAC systems and an arc flash and distribution system coordination study. G/BA worked for The John Buck Company, which is the building's property and project manager and leasing agent.

  • The last major upgrade was completed in 1992; thus, building MEP systems are nearly 25 years old. 
  • Floor-by-floor air conditioning units reject heat to a cooling tower. Our team documented existing conditions and made recommendations for potential improvements.
  • Options investigated included replacing the floor-by-floor units with similar equipment, or installing new units with chilled water coils in conjunction with more extensive central plant improvements (chillers, heat exchangers, pumps, riser modifications, and so on).
  • Logistics of the installation, including bringing equipment to a downtown high-rise building and minimizing tenant disruption, were evaluated and included in G/BA’s cost estimates. Our team also provided advice regarding available financial incentives from the local electrical and gas utilities.
  • In a separate project, G/BA performed an arc flash and distribution system coordination study for The Rookery’s electrical system. Every electrical panel was examined, and breaker characteristics were recorded for input into the SKM software.
  • Based on the findings, the facility is implementing labeling of all electrical devices with appropriate arc flash labels.