The genesis of the new Fort Belvoir Community Hospital in Fairfax County, Va., stems from a 1998 Pentagon study, which showed that consolidating various bases and military operations across the nation could potentially save the government $7 billion a year. In response, Department of Defense (DoD) officials created recommendations for the 2005 Base Closure and Realignment Commission (BRAC) to reorganize for greater efficiency and improve operations.
There had been other BRAC rounds in the past, as the process is governed under the Defense Base Closure and Realignment Act of 1990, but 2005 marked the U.S. Army’s largest organizational transformation since World War II and included a $13.5 billion planning, design, and construction program consisting of 440 projects.
As part of that process, the 1909 Walter Reed Army Medical Center in the nation’s capital was marked for closure and its functions were transferred to the $1 billion Fort Belvoir Community Hospital as well as the National Naval Medical Center in Bethesda, Md. Fort Belvoir also absorbed the functions of the newly closed nearby DeWitt Army Community Hospital.
HDR–Dewberry Joint Venture designed the new 1.3-million-square-foot hospital, which opened last summer. Jeff Getty, lead architectural designer and senior vice president at HDR Architecture, notes that the state-of-the-art facility responds to several newer trends. “Fort Belvoir is one of the first hospitals to include Army, Navy, and Air Force medical personnel and serve all of the military branches as part of the DoD’s joint-service facilities efforts.”
With a staff of 3,000, the Fort Belvoir facility handles more than 570,000 patient visits each year—including active-duty U.S. military members, veterans, retirees, and family members. But despite its massive staffing numbers and building size, the hospital has only 120 beds. “This speaks directly to a healthcare trend toward more care delivered on outpatient basis, and the DoD has always been a leader in outpatient care,” Getty says. “More than half of the space is outpatient family practice and specialty clinics.” In all, 55 primary and specialty care clinics are spread across four two- and three-story clinic building wings with a seven-story hospital bed tower at its center.
Another first for a military healthcare facility is the incorporation of evidence-based design (EBD) principles, which draw upon research to inform the planning and design process. The project incorporates features that help with infection control, patient and staff satisfaction, noise reduction, and wayfinding. The hospital includes plentiful daylight, bright colors, and nature themes to encourage patient recovery. In addition, the team leveraged the fact that the structures had to remain fairly low due to height restrictions of the adjacent Davison Army Airfield, and defined the building shapes with six outdoor healing-garden courtyards that offer views and physical connections to the natural environment.
HDR–Dewberry wanted to give the hospital exterior’s iconic stature while connecting it to Fort Belvoir’s existing red-brick structures.But as a government property that needs to perform for 100 years, it was also critical to ensure that moisture intrusion be avoided for occupant health as well as building longevity. A third restriction on the exterior was a strict construction time frame: Under BRAC, actions to close or realign a base must be initiated and completed swiftly, so the team had to have the facility operational by Sept. 15, 2011. A terra-cotta rainscreen system on the building enclosure addressed all of these objectives: the fired clay visually related to the military base’s masonry; the rainscreen’s design provided a moisture barrier; and its assembly was much faster than that of brick façades.
The team also selected metal panels to lend interest to the terra-cotta façades, emphasize different portions of the project, and soften the facility’s scale. “We looked at a number of different materials, but ultimately chose zinc,” Getty says. “Zinc was a maintenance-free, quality material with a long lifespan and similar performance characteristics to the terra-cotta. These qualities provided value for the Army Corps of Engineers.” More than 36,000 quartz-colored zinc panels, 1mm thick, cover 120,000 square feet across five structures in the complex.
The layered system consists of exterior metal stud framing, exterior fiber-reinforced gypsum-board sheathing, a thin layer of liquid-applied air-vapor barrier, mineral wool insulation, and subgirts that attach through to the framing. The rainscreen panels attach to the subgirts, but a 6mm separation between the rainscreen and insulation creates a ventilation zone for air movement.
“The air-circulated space between the rainscreen and outermost layer of the wall creates pressure equalization to prevent water from being drawn into the system,” explains Dan Friedman, HDR project architect for the exterior enclosure. “Any moisture that finds its way into the air cavity is either stopped by the insulation, evaporated out, or falls into a gutter folded into the panel that channels water downward.”
The zinc panels arrived on site as 1- by 4-foot, tongue-in-groove interlocking pieces that create a watertight flashing for the system. Component Assembly Systems in Landover, Md., performed exterior framing by assembling the finished zinc rainscreens. “We had to coordinate with the other components in the exterior wall systems to align joints, create proper water tight seals, and ensure proper dimensions,” says CAS project manager Stephen Lewis.
To expedite construction, the project was completed using an integrated design-bid-build process, which meant that design and construction occurred simultaneously. Component Assembly Systems’ first big push was to get the air-vapor membrane on top of the gypsum, which provided a watertight finish so that the team could start work on the interiors as quickly as possible.
For Lewis and his crew, the fast-track process added a layer of complexity. “During construction, a building’s thickness from the exterior to the sheathing can vary from plan,” he says. “We were coordinating prefabricated interlocking metal panels to 1/8 inch and they had to perfectly align with the terra-cotta panels, so there was no room for on-site alteration. Every panel that needed to be reordered to fit field conditions would take four weeks for fabrication.”
Ideally, Lewis would have preferred to spend more time coordinating shop drawings through building information modeling and obtaining their acceptance in full so the panels could be released for fabrication to avoid delivery and schedule issues. However, despite the trials of the constrained project timeline, the facility opened when scheduled. Fort Belvoir was constructed in just over three years, which is half the time anticipated to build a facility of this magnitude.
Fort Belvoir includes sustainable-design features and the team is seeking LEED Gold certification from the U.S. Green Building Council. According to Friedman, the exterior enclosure is helping the team meet the sustainable requirements. “The rainscreen offers many high-performance characteristics,” he says. “It’s made of 100 percent recycled materials, has 50 to 60 percent higher-effective insulation value for energy efficiency, and provides moisture control to eliminate mildew, which creates a healthier building for staff and patients.”
KJ Fields writes about architecture and sustainability from Portland, Ore.