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Big Ripples
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The client wanted the building to be a model of energy-efficient and environmentally responsible design so the project was designed for a LEED-Gold rating. According to Heifer International, the building uses 52 percent less energy than a comparable structure using standard construction methods.
"If we're going to have a lasting impact on ending world hunger, then everything we do must renew the earth and not deplete it," says Jo Luck, Heifer's president and CEO. "It's true whether we're working with people who want to be self-reliant or managing our own worldwide operations."
Form and Systems
One basic design strategy was to stretch the building east-west with a relatively narrow width, allowing good solar access and daylighting throughout the structure. There's also the idea of the building, which was laid out on radiating lines, tracking the sun, much like an inverted version of the Solar Hemicycle (Jacobs II) House by Frank Lloyd Wright. The benefits of the curve itself are more gestural than actual in both cases, but the arcing form gives the structure interest and focuses the site plan toward the entry point and the views toward the Arkansas River.
It was important to the clients, being a nonprofit concerned with world hunger, that the building project vitality but not ostentation — much as their name unabashedly retains the grounded connection to their mission. The architects approached this issue by exposing the structure, metal deck, and mechanical systems. These carefully detailed systems contribute to a graceful functional esthetic throughout the building.
The popularity of Heifer International has had its own ripple effect. Its success caused it to outgrow its former facilities in downtown Little Rock. The site they selected for their new headquarters was an old rail-switching yard with a jumble of derelict masonry buildings on the property. Years of industrial use had left the site contaminated.
Before construction could begin, the brownfield portions of the site had to be mitigated. After some initial investigation of reusing the existing buildings, the architects determined that they couldn't be incorporated successfully. However, 97 percent of the material — mostly masonry — was ground up and reused on site.
Heifer's Rippling Pond
One of the most distinctive aspects of the site design is the use of water. In his design "story script," Landscape Studio's Ed Blake poetically describes the progression of water into 24 "themes," each describing natural events or habitats along the course. Each theme has an educational message, enabling the visitor to experience the complex array of natural systems and processes.
Runoff water from the ground and areas of pervious paving filters into bioswales and then into a large waterway between the parking area and the building. This waterway moves around the building on three sides like a moat, giving the building the appearance of floating.
Water is also an important feature in the building design. All the water from the roof is collected in a huge cylindrical cistern and used for flushing toilets and other nonpotable applications. The architects designed the cistern as a centerpiece, spinning a main staircase around the structure. All three staircases are untempered — neither heated nor cooled — but encased in glass panels and stack-ventilated to protect occupants from the harsher elements.
Light and Air
The thin profile of the building allows daylight to penetrate deep into the interior, saving energy and filling the work environment with natural light. "The idea is that every person should have a piece of sky," Rowland says. The standard cubicle height was lowered to accommodate this visual connection.
The use of sunshades on the south facade provides a good example of the opportunities presented by the functional demands of sustainability. The shades protect the south offices from the harsh sunlight and they also serve as light shelves bouncing light into the interior through strip windows above the shelves. These elements contribute to the exterior aesthetic, giving depth and interest to the otherwise sleek building envelope.
The designers assert that it didn't make sense to install operable windows in the offices because in between the hot humid Arkansas summers and cold winters there are, on average, only 30 days annually when natural ventilation is practical.
However they did place operable windows in common areas of the building and at the more public areas at the ends. In one of the most captivating features of the design, the building gracefully "deconstructs" at the west facade leaving balconies and protective panels to read much like a literal section through the structure.
Focusing on strategies that have a 5- to 19-year payback period, the architects chose not to install photovoltaic panels initially. However, they accommodated the future installation of PV by sloping a portion of roof to an appropriate south-facing angle for future panels.
A stone's throw from the Clinton Presidential Library by the Polshek Partnership Architects, the Heifer building contributes another lyrical element to Little Rock's rejuvenated riverfront. A future phase will include a "Global Village" where the Heifer waterway will terminate in a park exhibiting traditional buildings from eight villages arranged around a great mound. That project is currently on the boards of Cambridge Seven Associates.
There is no question that, with increasing demands on resources and the environment, we must change the way we build. This challenge presents the opportunity to make buildings that are formed from regional materials, that are articulated to use the sun and wind, and that, like Heifer International, find ways to engender beauty in efficient design.
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Michael Cockram is an adjunct assistant professor of architecture at the University of Oregon. He is the director of the Italy Field School Program.
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