Restoration of Polk County Courthouse honored for preservation of Iowa’s historic public structures

OPN Architect’s exterior restoration of the Historic Polk County Courthouse was recognized on Sept. 15 by Preservation Iowa at the nonprofit’s summit in Davenport. One of eight awards, the Polk County Courthouse project was honored for the preservation of a public structure.

Designed by the Des Moines-based architectural firm of Proudfoot & Bird, the current Polk County courthouse was built in 1906. Constructed for $750,000 on the site of its 1858 predecessor, the Beaux-Arts style courthouse was listed on the National Register of Historic Places in 1979. Typical to the neoclassic style, the courthouse’s design incorporates overscaled cornices, swags and other sculptural details on a stone façade. The roof is characteristically flat with the exception of the clock tower and cupola emerging from the center.

As Richard Moe, National Trust for Historic Preservation, said: “When you strip away the rhetoric, preservation is simply having the good sense to hold on to things that are well designed, that link us with our past in a meaningful way, and that plenty of good use left in them.”

We couldn’t agree more.

OPN’s work at the historic courthouse is part of a multi-phased process that began in 2010 when we began working with the county to determine the viability of renovating multiple Polk County Courts system structures, including the historic courthouse.The resulting Fifth Judicial District Master Plan outlined a plan for the Justice Center, Criminal Courts, and Historic Courthouse, which addresses maintenance, life safety, and space concerns for the state’s largest county courthouse system used for both court functions and county administration. It honors the past while also providing for the future.

The first phase of the plan involved exterior restorations to the historic courthouse to address the issues of water entering the building as a precursor to the larger interior project scheduled to commence in 2018. Work focused on stone cleaning, stone spalling,and adding lead-coated copper detailing and flatlock to the balcony recesses, tower and at roof levels. Interior masonry of the tower was damaged; poultice for the salt extraction and repointing was completed in the tower above the occupied building below. The exterior stone surface had large amounts of salts, which caused microfracturing of the limestone through the mechanisms of inter-granular crystallization. OPN extracted the salt to prevent further damage to the stone material. We also conducted extensive tests to determine the gentlest means possible to remove biogrowth on the limestone.

OPN Architects is proud of our portfolio of historic restorations, preservation, and reuse. Like Preservation Iowa, we believe the preservation of Iowa’s historic resources is critical to our state’s future. Iowa is full of architectural treasures. In some cases, structures are worth saving because they are of architectural significance. In others, they are meaningful to a community’s fabric. The winners of this year’s Preservation at its Best Awards represent both. They rejuvinated city blocks, restored theaters and fire stations, repurposed a former post office, and revitalized downtown housing.

Congratulations to all of this year’s winners.