The U.S. Capitol Dome serves as a symbol of our country and our government. It was designed by Architect of the Capitol Thomas U. Walter, and is the Capitol’s second dome. Made of 9,909,200 pounds of cast and wrought iron, the Dome was anchored atop the existing Rotunda walls with 5,214,000 pounds of new brick masonry. Its iron columns were cast hollow, allowing some to serve as chimneys or rain downspouts. Work on the exterior was completed on December 2, 1863, when the last section of the Statue of Freedom was put in place atop the new Dome. The interior was completed in January 1865, when Constantino Brumidi finished his fresco, the Apotheosis of Washington.
Why does the Capitol Dome need renovation?
Because the Capitol Dome is predominately made of cast iron, exposure to rain, snow, sleet and sun causes damage to its exterior. Water infiltrates through pin holes in the Statue of Freedom, and through cracks and open joints throughout the exterior shell including: the tholos balustrade, the base of the cupola, and the boilerplate balcony level. Leaks into the interstitial space promote the rusting of the ironwork and the failure of the protective paint coatings. Decorative elements that give the Capitol Dome its unique character are rusting, and in some cases falling from the structure. If these repairs are not made, the artwork in the Rotunda, including the Apotheosis of Washington and the Frieze of American History, are at great risk of damage due to water leaks.
What is the purpose of the project?
This project is a critical step for stopping the current level of deterioration in the Dome’s cast iron as well as ensuring the protection of the interior of the Dome and Rotunda. The last significant exterior renovation of the Dome was performed in 1959-60 when it was stripped of its paint so the ironwork could be repaired and primed with a rust inhibitor. As part of its comprehensive project planning process, the Architect of the Capitol (AOC) plans to undertake a similar renovation between the 2013 and 2017 Inaugurals, pending receipt of funding. The restoration project includes removal of old paint, repairs to the cast iron and stone, and repainting.
What is the status of the project?
The Dome Restoration Project is designed as four phases: the restoration of the Dome Skirt (complete); the restoration of the exterior and interior face of the Dome shell; restoration of the interstitial space and infrastructure upgrades; and restoration of the Rotunda ironwork and stone surfaces. The AOC will soon publicize a solicitation for the remainder of the Dome Restoration Project. Pending receipt of funding, the AOC plans to award the exterior and interior face of the Dome shell portion of work in summer 2013.
Why is this project starting now?
Postponing the restoration would perpetuate the deterioration of the Dome. The flaking and peeling of paint will substantially increase resulting in an unsightly appearance. In 2010, it was noted that items identified in a 2001 study had further deteriorated, resulting in repairs that are more complex and costly. As conditions continue to deteriorate, the safety of visitors to the Capitol is threatened by falling objects. Installation of safety netting to the Dome Rotunda would be required to prevent injury.
How can we ensure the project delivers good value to the taxpayer?
The AOC is committed to maximizing taxpayer value, reducing the risk of cost overruns and delays, and minimizing disruption to the work of Congress. During the design of the project, the AOC employed an extensive review process of the contract documents to avoid future changes that may cause cost increases and delays, and a third party cost estimate was developed that supports the current budget. Additionally, the AOC is incorporating lessons learned from the work on the Dome Skirt, which was completed in 2012, on time and on budget. A key element to the success of the work on the Dome Skirt was the selection of a highly qualified contractor. A similar selection process will be used on this phase of the project. During the construction, a team of AOC personnel will ensure the contractor delivers a quality product through a diligent management process.
What are the benefits of the project?
The project will improve the quality of the Capitol Dome and provide protection from the elements for the next 50 years to preserve one of the nation’s most iconic structures. There is only one Capitol Dome, and the AOC is committed to preserving it for generations to come.
What will the Capitol look like during construction?
The project requires the installation of a scaffold system surrounding the entire Dome from the base of the Statue of Freedom down to the roof. The scaffold mimics the general shape of the Dome and will be covered with a white scrim. At night the lighting for the workers will shine through the scrim. At the interior of the Rotunda, a white catenary system in the shape of a doughnut will be installed above the Frieze of American History to protect the public. The doughnut configuration allows the Apotheosis to be seen during the restoration process.
When will this work begin?
Pending funding, the contractor’s mobilization with a bridge and tower system at the northwest corner of the Capitol is expected to begin summer 2013, with the erection of the exterior scaffold and installation of white catenary system to begin in the fall.