Clinton County Annex

The Clinton County Annex is a new 41,925-square-foot government facility designed to modernize county operations and improve access to essential public services. Delivered through Envoy's Build-Operate-Transfer (BOT) approach, the project provided Clinton County with a Guaranteed Maximum Price (GMP), reduced project risk, and a single point of accountability from concept through completion. Constructed on the historic downtown Frankfort square, the Annex replaced an outdated vacant building and now houses nearly all county administrative offices—including the Clerk, Treasurer, Assessor, Recorder, Commissioners, Courts, Surveyor, Archives, and Veterans Services—creating a centralized, efficient destination for residents. As part of a broader courthouse modernization effort, the project overcame the challenges of a dense urban site while preserving the surrounding historic environment, resulting in a facility built to serve Clinton County for decades to come.