In a Class of Its Own
Aluminum-Sheathed ‘Super Class A’ Building
Earns Highest Marks for Work Environment

Drive down I-270 just outside the Washington Beltway and you can't miss it: a gleaming monolith that looms over all other buildings at the gateway to Maryland's "Technology Corridor."

A testament to the boldness and splendor that can be achieved from the effective use of aluminum curtainwall, the Tower Building gives commuters a different look throughout the workday depending on the sun's position and the presence or absence of clouds. In fact, over 200,000 commuters a day pass the building and, no doubt, also take in lessee Bank of America's signage, which is posted on the building's highway side.

Image and presence were important to the building's developer, the Tower Companies, who encouraged architects Ben Kishimoto and Chris Gordon to pursue a design to help attract high-technology tenants. The result: a 10-story, 276,000-square-foot curtainwalled ellipsis. Perhaps the building's most arresting features are two aluminum plated sail walls that bisect the main structure and help give definition to the building's changeable shape when viewed from different angles.

"The dynamic shape of this building is meant to evoke forward progress—a perfect metaphor for its prominent position on I-270," explains Jeffrey Abramson, a partner in the Tower Companies.

"The building has a large footprint," notes architect Chris Gordon. "The shape diminishes the size of it. It's slender and pointed at two ends. You can't see the size of the building because of the shape of it."

Both architect and owner wanted a "clean, modern, well-designed" look for the building, notes Gordon, "and ended up selecting a unitized curtainwall system to achieve that. Once the decision was made to go with metal panels, plate aluminum was the only material that would achieve the flatness desired."

"We always use aluminum in our buildings because of its durability and the high degree of quality control," he added.

Because of the building's unique shape, a model was tested extensively in a windtunnel under a variety of conditions, including a 75 m.p.h. rain-accompanied wind. Curtainwall expert Carl Hensler oversaw the testing, which showed the building's performance on wind load at 20 percent efficiency over standard building code.

Considerable effort was undertaken to ensure the curtainwall—fully unitized, pressure equalized, and double chambered—was airtight and energy-efficient, says Hensler. Aluminum extrusions were ultimately sourced from Hyundai of South Korea, and involved the production of 56 custom dies of up to 8–9 inches in depth.

Super Class A Designation
The building's interior systems were also engineered to provide optimal energy efficiency, building performance, and amenities for the benefit of the tenants:

• Air quality—a 100 percent building-wide exchange of fresh air occurs every hour.
• Fenestration—low-e windows maintain a comfortable environment and allow in generous amounts of natural light.
• Acoustics—extra insulation was incorporated into the curtainwall's glass spandrels to deflect traffic sounds from the nearby highway.
• Technology—the building is wired throughout with advanced fiber optics.

So high is its overall performance that the Tower Building has earned the designation of "Super Class A," a new classification created by industry group Costar for top-of-the-line commercial properties.

"The Tower Building's energy-conserving, ecological, smart/green design will create a 'green image' for corporate tenants, and help them attract and retain young, environmentally aware employees. That's a major selling point given today's competitive job market," comments Abramson, the developer. "Today's workers want to know that their employers care about their health."

"Tower are very environmentally conscientious developers," says architect Chris Gordon, noting their commitment to using recyclable building materials, such as aluminum, and to providing a healthy indoor environment. He added that the biggest push for green buildings, in fact, comes from owner-operators such as Tower, "because they could be held liable in the coming years if a building is not healthy."

Still, Gordon says that the market for smart-green buildings is fairly limited due to a lack of education among the general public. "Studies have shown that occupants of healthier buildings are more productive and work longer hours. [But you need to] take that data and put it into the broker community and the business community."

The Tower Building appears to be doing its part to educate the public in that regard. Built on spec and completed in the midst of a recession, it nonetheless leased out fully within a year of opening.