Howard Hughes Medical Institute’s Janelia Farm Research Campus

Tucked into the landscape of rural Loudoun County in Northern Virginia is the Howard Hughes Medical Institute’s Janelia Farm Research Campus—a complex created to provide unique opportunities for the pursuit of cutting-edge biomedical research. The verdant setting of approximately 690 acres is the backdrop for an advanced research center, conference facilities, and housing for resident scientists, permanent staff, and visitors.

The facility evolved out of the Institute’s desire to establish a scientific community where researchers would be able to work without the intellectual and financial constraints usually imposed by traditional academic institutions. The intent was to offer an environment that would stimulate researchers from many disciplines to exchange ideas and collaborate in addressing the most pressing concerns of biomedical science today. Located just 40 miles northwest of Washington, D.C., Janelia Farm is designed to accommodate the Institute’s own investigators, a permanent research staff of 300, and visiting scientists. One of the chief criteria in planning the complex was to nurture fruitful interactions among researchers by presenting a physical environment that would encourage innovation and collegiality and enhance the opportunities to form self-assembled teams. The research areas also had to be flexible enough to allow for anticipated changes in the scientific activities to be performed there. Finally, the complex—to be constructed on farmland purchased by the Institute along the Potomac River in Ashburn, Va.—should be compatible with its surroundings and meet the highest standards of sustainability. Rafael Viñoly, whose design concept for the site was well suited to the Institute’s vision, was selected as the architect.

Once the core objectives were in place the project team was assembled. In addition to the architect, the team included, among others, Jacobs Facilities, Inc., project manager; Thornton Tomasetti Engineers, structural engineer; and Turner Construction Company, construction manager; as well as the Institute’s director, Gerald Rubin, and its architect and senior facilities officer, Robert H. McGhee.

Planning and design of the $500 million project, which began in January 2001, then became a collaborative process, a model, perhaps, of the process envisioned for the research teams. Members of the team met in intense, day-long sessions to determine the most desirable and viable building placement on the site, as well as architectural features and structural components, with in-depth exploration of each element before decisions were made. Ultimately, the design of the entire complex was driven by the Institute’s scientific and environmental goals.

The conservationist vision

In a conservationist approach to land use, the campus covers only 60 acres of the sprawling property, and is shielded from its nearest neighbors by the surrounding woodland. The buildings themselves were conceived not only to avoid intruding on the landscape, but instead to merge with it, so that the campus would barely be noticeable from the historic manor house on a nearby hilltop (the home of the original owners), and would not impede the view from the house. The centerpiece of the complex, the research facility, is in fact known as the Landscape Building because it meets this criterion.

Unobtrusive despite its size—almost 750,000 square feet—the four-level structure is set into a hillside and terraced to follow the slope. Facing north and overlooking a pond, its undulating silhouette echoes the rolling contours of the countryside around it. Most of the visible exterior is structural glass, and retaining walls at the rear and the ends of the building are faced in stone. The uppermost level is a rooftop garden planted with indigenous grasses and other vegetation, which gives the impression that the structure has sprung from the earth. To achieve the terraced effect, the building is stepped back 60 feet at each level, narrowing as it rises. Toward the front, a full-height, glassed-in, 8-foot-wide corridor runs along the 1,000-foot length of the structure, diffusing natural light throughout the interior. Glass-enclosed office pods, which admit additional light, alternate with terrace gardens on the second and third levels. The building houses laboratory space and state-of-the-art technical equipment, a vivarium, an auditorium, conference rooms and offices, administrative functions, and building support services.

Construction was underway by November 2002. As a result of a relatively compressed three-year schedule for the completion of the elaborate structure, work on the foundation began as soon as federal authorities were satisfied that the project would respect the local ecosystems, but before the final design was finished. However, due to soil conditions on the site, selecting the exact location for the building presented an initial challenge. In some areas, extremely soft soil or fractured rock beneath the surface raised questions of stability. These were resolved by increasing the size of the spread footings and excavating further to reach more stable layers. Elsewhere on the site, solid rock made it extremely difficult to install utility lines. Footing sizes were again adjusted, minimizing the need for excessive drilling or blasting.

The structure

To respond to the long spans demanded by the architectural concept, Thornton Tomasetti elected a hybrid steel and concrete structure. Much of the structural system on the north side is entirely steel, while much of the south side is concrete. Cast-in-place reinforced concrete was used for the basement and lower floors, and steel frame and composite decks for the upper ones. The S-shaped configuration of the building did not lend itself to conventional structural design, but instead dictated a curved column grid with varied column spacing ranging from 12 feet to 60 feet east and west and 22 feet to 33 feet along the length. Because of the terraced design of the structure, a 40-foot-high retaining wall was built from the first to the third levels and a 15-foot-high retaining wall from the third level to the roof, along the south side in the rear.

Located on the ground floor, the lowest level, are a lobby, a 250-seat auditorium, seminar rooms, a cafeteria and dining room, administrative offices, mechanical spaces, and the loading dock. In addition, there is an 8,000-square-foot vivarium and approximately 30,000 square feet of space for electron microscopy and nuclear resonance imaging. On this level, a 6-inch-thick slab on grade supports the administrative areas while an 8-inch-thick slab on grade supports the heavier mechanical and loading dock areas. Two 24-inch-thick isolated slab zones were also designed to accommodate the sensitive technical equipment and protect it from vibrations. The auditorium, which required a 100-foot-diameter clear-span circular space, is topped by a domed roof. Its outer walls, composed of architecturally exposed concrete, support 50-foot-long curved plate girders that converge at the center like the spokes of a wheel to form the dome, which in turn supports the vibration-sensitive laboratory space above it. A framed floor structure of beams and columns create the flat plane for the lab space to rest on. The plate girders also serve as transfer girders for the steel columns, supporting the landscaped rooftop. Behind the auditorium lies a 110-foot by 48-foot area that had to remain column-free for the installation of research equipment. The open space was achieved through the erection of a 17-foot-tall steel truss spanning 110 feet. To fit the curvilinear geometry of the building, the truss was fabricated in three segments with a transition at the connections. The floor diaphragms on the second and third levels were devised as transitional elements to resist the unbalanced forces of the truss. The size and shape of the truss made its erection an extremely laborious and time-consuming enterprise.

The second and third levels are comprised of 17- to 18-feet-high floor-to-floor and contain an open-plan lab area that is separated by the corridor from office and meeting room clusters. To allow for flexibility in program planning, the lab space was designed to be easily and efficiently reconfigured. Ordinarily, a laboratory configuration would not demand spans as long as 48 feet, but in order to accommodate the adaptable layout, the second level required a one-way concrete slab system supported by 48-foot-long beams running in a north-south direction. These sit atop concrete girders, with space between them to allow for mechanical ductwork. At this level, the long spans along the corridor were achieved by alternating column spacing at 20 feet and 30 feet.

On the third level, the need for flexibility was met by a custom-designed lab bench layout that necessitated an 80-foot by 48-foot column-free area. A structural steel plate girder system to frame the landscaped roof above these open-space labs was the obvious choice to deliver such long, clear spans. The steel columns supporting the plate girders were spaced at alternating 20-foot and 80-foot intervals, and the plate girders were cantilevered by 15 feet on either side of the 20-foot column spacing, resulting in 50-foot-long plate girder units joined by simple shear connections. Above this front steel system are the 32-square-foot, glassed-in office pods, which are supported by tubular steel columns and W-shaped steel beams moment-connected in both directions. The office roofs overhang the walls of the pods, creating a sort of sunshade to protect them from heat and glare. Interspersed with the offices are open-air garden cells that furnish more green space. The third level also features a 120-foot-wide by 100-foot-long parking garage, situated at the rear. The garage is partially slab on grade and partially framed slab composed of 60-foot-long beams with 8-inch-thick one-way slab.

Unique aspects of design

The structure’s 180,000-square-foot landscaped roof is perhaps its most noteworthy green aspect. The second-largest green roof in the United States, its natural vegetation mirrors the natural surroundings. Although a light fill weighing less than soil was used for the plantings, the long-span roof was still subject to heavy loading. To support these heavy loads, the reinforced concrete beams and the slab were post-tensioned with pre-stressing tendons.

The research center makes extensive use of structural glass, arguably Viñoly’s signature material. The 147,000-square-foot, stainless-steel-framed glass enclosure system made the project one of the biggest glass installations in the United States, requiring 85,000 manhours and extraordinary coordination among members of the construction team. To account for the localized aspect of wind loads and the thermal exposure to cold and heat, which could vary by 100 degrees in a given day, special aluminum and stainless steel details and joints were employed to allow for expansion and contraction.

Two monumental steel and granite staircases divide the structure into three portions separated by expansion joints, placed in proximity to the stairs. The glass-enclosed staircases connect the building’s entry level with the laboratory levels and the roof. The Landscape Building is linked to the 96-room conference facility north of it by a tunnel below the eastern stairs. This two-story, curved concrete structure, approximately 800 feet long, employs concrete columns at 20-foot spacing and an 8-inch-thick concrete flat slab. The transient housing, which includes one three-story studio building, seven multi-unit townhouses, and the director’s residence, complete the campus. Timber design was used for these buildings, which are clad in fieldstone and cementitious wood.

Successful sustainability

The design and construction of the campus reflect a consistent effort to put into practice the principles of sustainability. The most remarkable achievement was in creating a complex that blends so harmoniously with its environment. In addition, special care was taken to minimize the number of trees cut down during site preparation, and, in an unusual step, some trees were even relocated. Trees that had to be cut down were recycled by being ground into mulch or prepared for use in the onsite waste-to-energy plant. The landscaped green roof limited the need for drainage by serving as a vehicle for the retention of 95 percent of storm water, trapping rainwater in a network of pipes to irrigate the plantings. Furthermore, the structural glass exterior and roof panels, the glass enclosed corridor, offices, and staircases provide sufficient natural light to reduce the need for electricity. The positioning of the building, sheltered by the hillside, further lowers energy consumption. The pedestrian-friendly configuration of the site effectively limits the use of vehicles, thus cutting emissions on the campus.

Despite the challenges posed by the unique design and complexity of the facility, the project was completed on schedule, fulfilling the Institute’s objectives. Janelia Farm Research Campus had its official opening in October 2006.

Akbar Tamboli, P.E., is a senior vice president and principal of Thornton Tomasetti. He can be reached at 917-661-7800 or via e-mail at atamboli@thorntontomasetti.com. Umakant Vadnere, P.E., is an associate at Thornton Tomasetti. He can be reached at 917-661-7800 or via e-mail at uvadnere@thorntontomasetti.com.

Design & Construction Team

Owner: Howard Hughes Medical Institute, Bethesda, Md.

Architect: Rafael Viñoly Architects, P.C., New York

Structural engineer: Thornton Tomasetti, Inc., Newark, N.J.

MEP (Landscape building): Burt Hill Kosar Rittelmann Associates, Washington, D.C.

MEP (Conference hotel and transient housing): Flack & Kurtz, New York

Civil engineer: Dewberry & Davis, Fairfax, Va.

Landscape consultants: Roofscapes (Charlie Miller), Philadelphia; Paula Hayes, New York; Dewberry & Davis, Fairfax, Va.

Owner’s representative: The Mark Winkler Company, Washington, D.C. (Now Duke Realty, Alexandria, Va.)

Project manager: Jacobs Facilities, Inc., Washington, D.C.

General contractor: Turner Construction Company, Washington, D.C.

Steel fabricator: Hirschfeld Steel Company, Inc., San Angelo, Texas

Concrete contractor: Miller & Long, Bethesda, Md.