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The site location — on the edge of campus, flanked by public streets on three sides — offered the perfect setting to connect the two communities. The building relates to the city through its towering scale and corner siting, while it interacts with the campus by using smaller scale textures and materials. In weaving the city and campus, the building itself became a woven basket.

"The basket and weaving was used as a metaphor, a common denominator between the varying cultures of Auckland and AUT," explains Mac Kellar. "Woven from flax and designed for specific functions (harvesting, catching eels, carrying), the basket has always been a vital commodity for the Maori. The business school is like a basket of knowledge, gathering and containing knowledge."

The Basket-Weave Skin

Although the northwest facade does indeed appear at certain times of day to be woven, it is not and was never meant to be, says Mac Kellar. "We abstracted the idea and layered glass reinforced concrete (GRC) panels over the facade. We wanted sunlight and shadow to be part of the design, so we used computer modeling to design the panels so that they change throughout the day. By late afternoon, the play of light and shadow results in a three-dimensional woven effect."

Presumably, this effect could not be achieved during the entire day, so the target time period coincided with students and citizens returning home after a long day — a lovely effect, if more ephemeral than a true basket woven of native flax. Earlier in the day, the panel system appears more staid, but it presents an engaging visual texture nonetheless.

Along with suggesting the basket metaphor, the panel system functions as a sun screen for the building's curtain walls. While metal may currently be the industry standard for sun screens — this facade actually looks metallic at most times, from most angles — JASMAX chose GRC instead. This material was selected partly for its light weight (less structure), partly for its light color (less heat gain), and partly for its sound insulating properties (less street noise).

There is an internal steel frame cast within each panel, with fixing lugs projecting through the panel. These lugs are bolted to a system of external Vierendeel trusses. To make the trusses as slender as possible while still supporting panels that would block enough sunlight, Mac Kellar says the challenge was to "strike the right balance between angle and steel member size." The magic number? Eighteen degrees from the building face.

Through this 18-degree gap, occupants get regular exposure to sunlight and views out to the city. Slotted openings within the panel faces strategically locate additional light and views in appropriate interior spaces. These openings are kept narrow on the outside of the panel, but they splay toward the inside in order to allow a minimal amount of light to have the maximum effect on interior illumination.

Material Benefits

JASMAX kept environmental sustainable design (ESD) in mind during the entire design process. Mac Kellar recalls: "ESD requires the project be considered as a whole. While we did not push ESD to the limit, the prime area we targeted was reducing energy costs for lighting, heating, and cooling."

The facade design is a direct response to this objective, and Mac Kellar says that it has already been paying off. "Although achieving this goal required a higher capital cost, the long term savings are enormous both from a running cost and as a cost to the environment. To date, the facade is outperforming expectations, and we are still measuring the benefits."

While the sun screen is the most obvious sustainable strategy, many more lurk just behind it. Initial programmatic decisions such as flexible-use spaces, moveable walls, and high-density planning contribute to the building's ability to make the most efficient use of its area.

JASMAX also minimized the amount of paint needed by selecting building materials with raw aesthetic value, such as sustainably harvested wood wall paneling in the public areas. Concrete use was maximized, both to avoid finishing and to ensure the use of an inherently local product. Where carpet was required, recyclable carpet tiles were specified.

"The client absolutely loves the outcome," declares Mac Kellar. "They achieved everything they set out for and more. The contractor's site manager was also very interested in the design and put a lot of energy into achieving the highest level of quality. The staff members love going to work and students love the place and its energy."

Winning awards, saving energy, and energizing both builders and users — what more can we ask for? Interestingly enough, this green building also came in on time and under budget.   >>>

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Leigh Christy is an architect and writer living in Los Angeles.

SUBSCRIPTION SAMPLE The new Auckland University of Technology Business School, designed by the architecture firm JASMAX. Photo: Vincent Kar Shading panels with slits for views. Photo: Vincent Kar Panels mounted at an 18-degree angle on shallow trusses. Photo: Vincent Kar View out from behind a panel. The slits are splayed to augment interior daylight. Photo: Patrick Reynolds Photography Ltd. View to the city of Auckland between exterior panels. Photo: Patrick Reynolds Photography Ltd. Sustainably harvested wood wall paneling graces the public areas. Photo: Vincent Kar Circulation. Photo: Vincent Kar Massing schematic. Image: JASMAX   Click on thumbnail images to view full-size pictures.