Congress will cover the Capitol’s dome in scaffolding in November as part of a two-year restoration to fix more than 1,000 cracks that have developed over the decades, the building’s administrators said Tuesday.
Most of the work, budgeted at $60 million, will be done at night and on weekends to avoid conflict with congressional business and public tours. Tours of the dome will be canceled, but the rest of the building will be open.
“As stewards of the Capitol for the Congress and the American people, we must conduct this critical work to save the dome,” Architect of the Capitol Stephen T. Ayers said in a statement. “From a distance the dome looks magnificent, thanks to the hard-work of our employees. On closer look, under the paint, age and weather have taken its toll and the AOC needs to make repairs to preserve the dome.”
The work makes the Capitol the latest major landmark to be enveloped scaffolding. Most notably, the Washington Monument, which stands 14 blocks away on the Mall, is undergoing repairs for damage caused by the August 2011 earthquake.
The scaffolding on the Supreme Court was just disassembled after more than a year of repairs.
At the Capitol, the restoration will remove old paint and repair the cast iron dome, which has small leaks, before repainting and weatherproofing, said Justin Kieffer, a spokesman for the Architect of the Capitol. Without the repairs, both the Apotheosis of Washington and the Frieze of American History paintings on the dome’s interior are at risk of water damage, the architect said.
The current dome was completed in 1866, replacing an earlier, squatter version with the soaring cast iron landmark that stands today.
Working with cast iron presents unique challenges, said Guy Gugliotta, author of “Freedom’s Cap: The United States Capitol and the Coming of the Civil War.”
For example, cast iron cannot be welded; if it’s heated past a certain temperature, it will melt instead of join together. Another problem is that it rusts quickly when exposed. Once the paint is removed, workers will be working against the clock to fix cracks and repaint before the dome begins to rust, Mr. Gugliotta said.
While the workers face many challenges, working on such high-profile, iconic architecture leaves no room for error, Mr. Gugliotta said.
“You’re not allowed to make any mistakes because it’s the Capitol dome. You have to be sure of what you’re doing before you start,” he said.
The outside scaffolding will extend from the base of the Statue of Freedom that crowns the Capitol to the base of the dome, the release said. Scaffolding also will be erected on the west side of the Capitol to help bring materials up to the dome. That means visitors standing on the Mall between the Washington Monument and the Capitol will see scaffolding on both sides.
“It will still look cool at night with the lights, but the main points are to be safe and provide the best method,” Mr. Kieffer said. “It’ll be great to see, you’ll still be able to see dome through the scaffolding, which is a very beautiful, iconic image across the world.”
On the inside of the Rotunda, a “white canopy system in the shape of a doughnut” will protect the public from falling construction debris while allowing visitors to still see the Apotheosis of Washington painting in the center.
A covered walkway through the middle of the Rotunda will be built while the canopy is being put up and taken down.
Despite the cracks, Mr. Kieffer said the dome is structurally sound and safe for visitors and tenants. The dome was last restored in 1959 and 1960, which could cause another problem for workers this time around: lead-based paint.
“It is possible there might be several dozen coats of lead-based paint on the dome. They’ll have to clear that off,” Mr. Gugliotta said.
The joint contract for more than $40 million was awarded in September to Turner Construction Co. and Smoot Construction, with an additional $20 million for contingency costs and other projects costs included in the total budget, Mr. Kieffer said.
However, the money doesn’t matter when talking about preserving the history of the country, Mr. Gugliotta noted.
“Our buildings are very important to us, probably more so than other countries,” he said. “To me, it’s something you pay what it costs, and I don’t think anyone would begrudge the money.”