For the average person, the phrase "office park" likely conjures the tiresome concrete blocks that have proliferated across the country since the middle of the twentieth century. But for the architects at Kohn Pederson Fox Associates (KPF) and their client, real estate development company Hampshire, an aging office park in a quiet New Jersey town offered an opportunity to rethink the oft-maligned building type. The result is Centra at Metropark, also known simply as "Centra," the keystone of a master plan by the New York arm of the ardently international KPF. Though Centra works on a significantly smaller scale than some of the firm's larger projects, the concepts it engages—particularly its holistic treatment of site and structure—remain the same.
Location Iselin, New Jersey (Raritan Bay watershed)
Gross area 110,000 ft2 (10,219 m2)
Completed April 2011
Cost $16 million
Annual purchased energy use (based on simulation) 47 kBtu/ft2 (537 MJ/m2), 31% reduction from base case
Annual carbon footprint (predicted) 13 lbs. CO2/ft2 (63 kg CO2/m2)
TEAM & SOURCES
Glass Viracon, clear, VNE 15-63; grey, VNE 3-63
Flooring Duro-design, Marmol cork flooring; Kaswell, reclaimed White Oak end grain
Carpet Tandus, Full Volume
Centra's neighbors offer a glimpse of the office park in its natural habitat: vast parking lots and treeless plots with little differentiation of scale or level. Indeed, Centra differs so vastly in form and appearance from most office blocks that it hardly seems fair to call it by the same name. But while it may look radical beside its less glitzy counterparts, Centra's DNA is essentially the same as that of its neighbors: KPF repurposed the original structure—an uninspired, 1980s building with rows of windows along its sides—and stripped off the existing enclosure. The building's floors and steel skeleton were preserved and wrapped in a shell of tinted glass. Then, KPF crowned the newly clad building with a 10,000-square-foot, L-shaped fourth level. The joining of the old and new structures creates a large, central oculus through which light falls into spaces below. A desire to curb both cost and waste inspired the retrofit, says KPF senior designer Hugh Trumbull. "It's a much less expensive option, and it's also the option that makes the most sense for a client who wants to create an environmentally responsible building," he explains, emphasizing that LEED certification, though an end goal, did not take precedence over smart, responsible design choices. Structural engineer Stephen DeSimone, of DeSimone Consulting Engineers, concurred. "Clearly, saving and reusing a lot of the existing structure is, from our standpoint, good, sustainable design practice," says DeSimone. "There's just that much less waste going into landfills. And you're recycling, at a zero-energy cost, all the existing structural steel and concrete."
The extensive remodel didn't stop with the building; manipulating the landscape also became a crucial aspect of the redevelopment. Two lightwells featuring rainwater gardens—one at the center of the entry plaza under the rectangular oculus, and another at the site's northwestern edge—are major features of the building plan. These sunken spaces provide basement offices with much-needed light and air, a boon for workers who are often sequestered indoors for long periods of time. They're also good places for quiet contemplation and recreational use. The smaller of the two lightwells further serves to muffle the noise of traffic on the busy thoroughfare beyond the wall. In the building's original iteration, this road ran directly alongside workspaces, and the view from inside was a bleak one. "There was a real desire to try and recapture and make useable a lot of the below-grade spaces," says DeSimone. "So we ended up creating openings in the existing foundation walls." Because the creation of each lightwell required a good deal of earth moving, the excised land was used to create berms that, along with a limestone pyramid on the site's western edge, help break up the horizontality of the site.
These lightwells, however, also created a problem: access to the main entrance now had to traverse the hollowed-out space. So KPF designed a bridge-like portico that spans the sunken space below. Creating a bolder main entry was an added bonus. "So many office parks have tiny, nondescript entrances," says Trumbull. "We wanted to create a sense of place here." A three-pronged column also lends an air of grandeur to the stepped entry plaza. When asked about any structural roadblocks the tree-like column presented, Trumbull gave a wry smile. "Well, it's a bit like a waiter balancing a large tray on his fingers. During the development process, we wrestled with how to build it: column first or addition first," Trumbull says, referring to the protruding fourth-level addition that the column supports. In the end, the column was fabricated and put in place after construction of the new fourth floor was finished. "We had to put in falsework to support the erection of that steel, until the column was actually ready to be installed," says DeSimone. "So that was a bit of a wrinkle from a sequencing standpoint."
Interior spaces, too, have a lush quality uncommon to most office blocks. KPF specified a low-VOC finish for walls, some in a bright green that, along with ample daylight, give the lobby a cheery, open disposition. FSC-certified, end-grain wood flooring contributes further to the industrial but sophisticated aesthetic. These small touches go a long way toward proving "green" need not be granola, explains Emily Kildow, senior project manager at environmental consultancy Viridian. "Waterless urinals are usually a pretty hard sell," Kildow joked, but, she explained, Hampshire was determined to do as much as possible to reduce the building's energy and resource use.
Though Hampshire has yet to find tenants for Centra in today's challenging market conditions, Trumbull and Kildow each expressed their optimism. "Potential tenants will have to reduce their lighting efficiency by at least 10 percent over ASHRAE, use low-VOC paints, coatings, and adhesives," explains Kildow. "They'll need to do everything they can to keep the integrity of the base LEED certification." Centra is one point shy of reaching LEED-Platinum certification for core and shell, and the design team is working toward achieving the additional mark. In the meantime, the search for occupants continues. "We're finding that interested prospective tenants are coming to us and saying, 'what more can we do?'" says Trumbull. "And that's a great thing."