Polk County Historic Courthouse Interior Renovation
Polk County Historic Courthouse Interior Renovation
Polk County Historic Courthouse Interior Renovation
Polk County Historic Courthouse Interior Renovation

Polk County Courthouse Interior Renovation

Des Moines, Iowa

37,000 GSF

Originally built in 1906, the Beaux-Arts-style Polk County courthouse was listed on the National Register of Historic Places in 1979. It went through a multi-phase renovation which began with the exterior, which was completed in 2015. The next, much larger phase focused on the interior renovation, which was completed in 2022.

Alvine Engineering modernized the aged, essential systems and services, while maintaining the unique architecture and historical value of the building by designing as unobtrusive solutions as possible.


  • HVAC system replacement provided high occupant comfort with low energy costs, including courtrooms and judge’s chambers with individual control and ventilation provided by a dedicated outside air system that incorporates energy recovery.
  • Designed plumbing systems, including domestic water heaters, throughout the building for increased efficiency and modernization.
  • Electrical service throughout the facility was upgraded, including distribution panels.
  • Retro-fitted existing, historic light fixtures to LED and provided new, custom fixtures to replicate historic light fixtures.
  • 93 LED luminaries were installed for architectural facade lighting, including ground-mounted flood lights, building-mounted flood lights, and in-grade-mounted luminaries.
  • Faster, more efficient communication and data sharing was accomplished through the creation of telecommunications spaces and a complete optical fiber system.
  • Electronic access control design monitors parameter doors and critical doors within the building through the use of card readers, door sensors, and field control panels.
  • Acoustical analysis included acoustical modeling of the spaces to properly evaluate reverberation time, speech intelligibility, and sound levels.
  • Audiovisual system coordination and supporting infrastructure design included digital signage, room scheduling, and content delivery systems.

Photography credit: OPN Architects

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