CAPITOL IMPROVEMENT

Virginia’s Symbol of Liberty Celebrates 400 Years With Historic Preservation.

Design and construction team uses ingenuity and imagination to deliver the complex program needs while preserving the richness and beauty of the state’s Capitol in Richmond.

Thomas Jefferson likely would be proud and impressed with the ingenuity behind the three-year renovation and expansion of Virginia’s State Capitol in Richmond. 

The multitalented Jefferson, who designed the central component of the 89,000-sq-ft building on Shockoe Hill overlooking the James River in the 1780s, envisioned the Capitol as an enduring symbol of liberty and justice that “will be worthy of being exhibited alongside the most celebrated remains of antiquity.”

Jefferson’s design inspired countless other civic buildings as the nation he helped create expanded. 

A 1904-1906 modernization of the Virginia Capitol added monumental granite steps to the columned south portico and wings for the legislative chambers, while air-conditioning and electrical system upgrades arrived in the 1960s. 

Otherwise, most of the changes made to the structure were a result of age and deterioration, from corroded pipes and outdated utilities to moisture intrusion in the walls. 

In addition, working space for legislators and the governor was virtually nonexistent, as were options for disabled access. 

And with the Jamestown Settlement’s 400th anniversary celebration approaching, state officials worried that a new generation of visitors might find a Capitol building that did not live up to its architect’s lofty aspiration.

“It was time” for the $100 million program that began in April 2004, says Richard F. Sliwoski, director of the Virginia Department of General Services. “But we faced a rather formidable challenge. How do you restore a treasured state and national landmark?

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Fitting room

A substantial amount of imagination was necessary to approach the inherent constraints of a complex historic preservation project, particularly the limited amount of space available to integrate modern building systems. Overhead elements were out of the question in the historic areas and legislative chambers, while 4-ft-thick brick walls and limited interior space left few options for vertical shafts.

“A new building with all this modern technology would be much larger than the space available in the Capitol,” says Ronald Staley, vice president of the Christman Co. of Lansing, Mich., which served as construction manager in a joint venture with Gilbane Building Co. of Richmond. “A half-inch was a lot of room to us.”

For example, there was more mechanical equipment and ductwork to be installed than there was available attic and interstitial space, which forced the redesign of several areas. Rather than attempt to tunnel beneath the building to install piping and other utilities, the project team elected to excavate many of the ground-floor rooms by 3 to 4 ft and install a raised-pedestal floor system atop a new 4-in concrete slab. 

The approach not only proved easier to complete and preserved the original floor-to-ceiling heights, “it’s also a more flexible system that provides easier access for maintenance,” Staley says.

Workers also discovered that a sealant-coated Portland cement-based stucco was used on the Capitol’s exterior, and any moisture that got behind the sealant had only one way out—up and through the interior of the building’s  walls.?

“It was like the building was weeping for joy,” Sliwoski says of one test strip. “There were literally rivulets of water coming through the brick.”

That required more extensive tuckpointing to repair the mortar and full replacement of the exterior stucco. While most of the troublesome coating came off with the old stucco, terra cotta areas were given a chemical treatment to soften the sealant before they were power-washed clean. 

Although these issues added several months to the construction schedule, they also afforded time to address one of the project’s more welcome surprises: the discovery of Jeffersonian woodwork, which most experts believed had been taken out during the 1904-1906 renovation..

“Forensic testing of the paint layers revealed that vast majority of millwork in the rotunda and old Senate chamber was original, dating from the 18th Century,” says George Skarmeas, director of historic preservation for Hillier Architecture, Philadelphia, and the renovation program’s supervisor. “It was a remarkable find, but we had to quickly decide how to handle this discovery without interfering with the ongoing renovation.”

Making the most of a grant secured by the nonprofit Virginia Capitol Foundation, a team of preservationists carefully removed paint from the millwork. “That gave us a perfect record of what had happened to the wood over the past 200 years,” Skarmeas says. 

After extensive documentation, the wood was repainted in colors matching those used in the 1904-1906 renovation.

Expansion strategy

No one disputed that the renovation had to address the Capitol’s cramped working conditions, or that underground construction would be required to prevent diminishing the visual prominence of Jefferson’s “Temple on the Hill.” However, the landscaped Capitol grounds afforded no convenient location for the expansion. 

At first, the least disruptive site appeared to be directly behind the building’s north side. Skarmeas wasn’t so sure. “Because the original brick foundations are only 4 ft deep, excavation would have required extensive underpinning,” he says. “That would have added to the project’s cost and still left the building foundation vulnerable to movement and cracking.”
 
Instead, Skarmeas looked to the south and the hillside in front of the Capitol’s famous south portico, where site conditions were more favorable.

After the temporary removal of the 24 granite steps and installation of pressure grout injection points beneath the foundation in the fall of 2004, the project team began a 30-ft-deep excavation 5 ft from the building’s front. 

A structural concrete slurry wall with tiebacks helped stabilize the soil as excavation proceeded, while a network of real-time precision laser prisms kept an electronic eye out for even the slightest movement as approximately 20,000 cu yds of dirt were carved from Shockoe Hill.

“The most movement we had was about 4 millimeters, about half the limit for an alarm,” says Staley, adding that grout was injected only once as a precaution. “We found that when the slurry wall was completed, the building had actually returned to its original position.”

The excavation tapered to grade at Bank Street 380 ft away. Construction then began on the 27,600-sq-ft, steel-framed concrete extension.  Built on spread footings with 12- to 14-in. walls, the extension slopes up the hill from Bank Street. 

Approximately 10 tons of backfill covers the extension, with Geofoam placed at elevation break points to help relieve soil pressure. The restored hill includes plantings, paved pathways and other landscape features introduced in the early 1800s and after the 1906 renovation.

Aside from the columned-secure entrance at the foot of the hill, there’s no visual evidence that this approximately 2.5-acre “green roof” conceals a new museum; workspace for legislators and the media; multipurpose rooms; and a series of stairs, ramps, and elevators that bring visitors up to a new first-floor entryway beneath the restored monumental south portico steps.

The start of 2007 saw the project team putting the finishing touches on the restoration work and readying the new underground facilities. Both houses of Virginia’s General Assembly are scheduled to convene in their renovated chambers on April 4.
“Visitors will be able to experience Virginia’s Capitol the way Jefferson wanted,” Sliwoski says. “More important, the building’s enhanced functionality also fulfills his vision of a government that is both responsive and accessible to its citizens.”