University of Iowa’s Old Capitol dome will get new gold this summer for $500K

IOWA CITY — The University of Iowa will regild the dome of the Old Capitol this summer after failure of gold leaf installed in 2003.

OPN Architects, of Iowa City, recommended regilding at a cost of $504,375, compared with putting on a gold-colored sheet metal roof, which the firm estimated to cost $681,914 and take another year because of supply chain delays for sheet metal.

“After consideration of these options, our recommendation is: Option 1: Regilding the dome,” OPN wrote in an 18-page report made public Thursday. “This is the option that aligns with the budget and schedule for the project.”

The UI plans to put the project out to bid Feb. 8.

Work removing existing gold leaf and underlying lead would start in the spring. Gold leaf would be applied in the summer when temperatures are between 45 and 90 degrees — necessary for quality application, the report states. The project would be done in August.

The Old Capitol Building, for which the cornerstone was laid on July 4, 1840, was to be the hub of state government after Iowa City was chosen as the state capital in 1839.

The original dome was copper, but the UI paid $200 in 1920 to have 6,500 3-inch gold leaf pieces applied to the surface, The Gazette reported in 2001. Periodic regilding has happened since, with the UI paying $304,000 in 1993.

Nov. 20, 2001, contractors using open flame torches and heat guns to remove asbestos and paint from the dome accidentally started a fire. The blaze flared through the golden dome, bringing students, faculty and residents to the Pentacrest in downtown Iowa City to watch the fire in dismay and horror.

The fire also ignited years of legal battles over who would pay the $1.3 million restoration cost. In 2018, UI settled for $600,000 from six contractors. A new dome crowned the Old Capitol in February 2003.

The 12,000-pound wooden structure was gilded in a hangar at the Iowa City Airport and then hoisted to the top of the building. Conrad Schmitt Studios, of New Berlin, Wis., did the work in 2003.

Gold leaf is supposed to last 30 to 35 years.

To study why the 2003 gold leaf was failing 20 years into its life span, OPN went up on the roof to get a closer look. The report includes photos showing where its staff used tape to try to peel away sections to see how solidly the leaf was stuck to the dome.

“Based on these observations, the separation for this dome is occurring above the lead coated copper to the clear primer,” the report states. “This type of failure exposes the lead to the air, causing this surface to oxidize followed by expansion leading to more loss of gilding.

“In order to achieve a uniform, satisfactory gilded finish, it is necessary to, at a minimum, remove the existing gilding system down to the base metal,” the report states.

Gilding is a specialty craft done by a limited number of studios. Michael Kramer, president and founder of the Gilders’ Studio in Olney, Md., told The Gazette in October even fewer studios focus on large-scale outdoor projects like building domes.

“It was probably more prevalent in the late 1800s into the early 20th century to gild exterior ornament,” Kramer said. But “we gilded a new building in Dubai a few years ago.“

The Gilders’ Studio custom orders its gold leaf from an Italian company, which uses electric hammers to beat an alloy of mostly 23 3/4-karat gold into thin sheets that are put on rolls for application. The leaf is so thin a stack of 10,000 sheets is no thicker than a dime, Kramer said.

OPN recommended the contractor hired for the 2022 job use scaffolding and industrial rope access for the project, which is a similar process used for regilding the Iowa Capitol dome in 1999 in Des Moines.

“After removal of the current gold leaf, the sheet metal would receive a primer and two topcoats tinted to yellow base then the size (product used to adhere gold leaf to primer) and new gold leaf would be installed,” the report states.

Option 2, which the UI did not choose, was removing the existing metal roof and replacing it with a pre-finished gold-colored sheet metal. The life span of the metal roof would have been shorter than that of gold leaf, the report states.

This new metal roof could have been anodized aluminum, pre-finished steel or aluminum or copper with high-performance gold paint, which would “not have the same shine as gold leaf while the 20-year life span is still less than the gold leaf.”

Using sheet metal would add at least eight months to the project because of supply chain delays, the report states.

The UI paid OPN $23,500 for the dome study and report. The money for the UI dome restoration will come from the Treasurer’s Temporary Investments/Building renewal funds.

Comments: (319) 339-3157; erin.jordan@thegazette.com