Having just celebrated its 100th birthday last year, the Russell Senate Office Building is looking really good for its age. But, to keep it in tip-top condition, the Architect of the Capitol (AOC) spent some time studying the building's exterior in preparation to clean, repair and restore the exterior envelope of this historic Senate Office Building.
As part of their evaluation of the exterior conditions today, staff looked at the following architectural features: marble and granite facades; marble balustrades; courtyard limestone; mortar and caulking joints; decorative metal lighting and railings; wood windows; and bronze doors.
No Stone Unturned
"Our staff left no stone unturned, so to speak, when examining the Russell Building," said Martin Shore, preservation architect in the AOC's Design Services Division. "In addition to surveying the façade from the ground with high-powered binoculars, we brought in a 150-foot crane, allowing our architects, engineers and materials experts to study the building's conditions at its highest reaches up-close."
Shore noted that material samples were sent to laboratories to identify the stone's properties such as strength, water absorption and composition.
In addition, each of the Russell Building's 622 windows were surveyed during off-hours and weekends.
Given that most of the windows are original to the building, the Senate Superintendent's Office was determined to find an approach to improve the windows' energy efficiency that also was sensitive to the building’s original design.
Balancing the AOC's goals for sustainability, reducing energy consumption and historic preservation, two state-of-the-art computer software packages were incorporated in the study. The first application performed energy model calculations while the second estimated future expenditures (called "life cycle costs") for the next 40 years.
Using these computer programs, three scenarios concerning the historic windows were tested:
- Repair the existing windows,
- Retrofit the existing windows with insulated glazing, or
- Replace the windows with new energy-efficient windows
"The results were unexpected," said Shore. "The energy modeling and life cycle cost programs showed that retrofitting the existing windows with new glazing was, in fact, the most cost-effective, energy-saving option. And from sustainability and historic preservation perspectives, the retrofitting option was desirable because original building materials would be maintained and preserved."
In the past, historic buildings were torn down and replaced, as were tens of thousands of historic windows.
Today, the concept embraced by the AOC, sustainability experts and preservationists is 'embodied energy.' That is, the total expenditure of energy involved in the creation of a building and its materials is considered. When a historic building is torn down and its components, such as windows, thrown away, the embodied energy incorporated in that building is also discarded. That translates into a loss of both money and energy already invested. The old growth wood originally used for the Russell windows is considerably stronger than wood grown today. Therefore, it is more cost-effective and sustainable to keep the historic windows than buy new ones.
With the study results in hand, the AOC will now use the information collected as it plans the design and construction phases of the Russell Building's exterior cleaning and restoration. One of the AOC's main objectives is to create a phased plan to complete the work over several years. This approach will minimize disruptions to the building's occupants and will help to manage the project's cost and schedule.
"This is just one of the ways we are working to identify and implement long-term projects that will fulfill our mission to care for the historic buildings entrusted to our care, and attain required energy saving goals, while providing Congress with the best return on its investment at the same time," said Stephen Ayers, Acting Architect of the Capitol. "This type of holistic planning approach is essential when working with historically significant buildings like the Russell Building."
While passers-by won't see scaffolding surrounding the Russell Building in the immediate future, the AOC will be working diligently to develop a plan which will ensure that the Senate's first office building will be around for 100 more years. And while it will be more energy efficient, it will maintain its distinct historical character as it ages gracefully.