Alten Construction, a Richmond-based commercial construction company, recently finished construction on the historic Napa County Courthouse, with a team that also included Sonoma County companies.

Construction on the $13 million project began in September 2017 and was wrapped up in January. The facility had been closed since August 2014 following the South Napa Earthquake, which caused extensive damage to the historic courthouse. A grand reopening ceremony for the newly restored courthouse was held Jan. 22.

The project’s consulting team included AECOM of San Francisco; TreanorHL Architecture, also of San Francisco; Santa Rosa-based ZFA Structural Engineers; and TLCD, also of Santa Rosa.

The 18,000-square-foot structure consists of an 1878 historical building that had been unoccupied since the earthquake. An addition was later built and is still in service for the county court.

The repairs included deconstruction, structural, mechanical, electrical, fire protection and interior finishes. In addition to repairing the courthouse damage, the project also included the 16,000-square-foot courthouse historical renovation, structural repairs and reconfigured, ADA-compliant restrooms.