You don't necessarily associate either developers or ultrasustainable buildings with the L word. But Tony Gulliver, developer of 1 Bligh, clearly loves this building. Always has. It was, he says, love at first sight. From the moment he saw the model emerging from its box, he loved its greenness, its elegance, its prestige, and its subversive nature—not necessarily in that order. Indeed, what distinguishes this building as fine architecture is that these qualities are all interlinked.
Location Sydney, Australia (Parramatta River watershed)
Gross area 492,556 ft2 (45,760 m²)
Completed July 2011
Cost $206 million
Annual purchased energy use (based on simulation) 34 kBtu/ft2 (381 MJ/m2)
Annual carbon footprint (predicted) 6.2 lbs CO2/ft2(30 kg CO2/m2)
Program Child care, cafés, offices, underground garage
TEAM & SOURCES
Elevators Otis (custom)
Carpet Interface Equilibrium
Concrete finish Lasur Betocare Products (Germany)
The model moment marked the finale of the "design excellence" competition, by which time the process was well under way. The location, within Sydney's Golden Triangle (defined by Renzo Piano's Aurora Place, Norman Foster's Deutschebank, DCM's Governor Phillip Tower, and Kohn Pedersen Fox's Chifley Tower), had been selected. Five sites had been bought and amalgamated, their leases arranged to time out with the next demand cycle (2010–11). And the city's preliminary bulk-and-massing approval had been achieved.
The brief was for a sustainable office tower, 4.5 stars or higher on the National Australian Built Environment Rating System (NABERS) scale because, says Mike Russell, development manager of the building's owner, Dexus Property Group, "we knew the tenants wanted it." Prestige tenants, that is—banks and government departments. NABERS is a system managed by the New South Wales government that rates buildings all over Australia on the basis of their actual, proven performance.
Holding a design competition wasn't entirely altruistic. Sydney's planning rules offer developers an extra 10 percent of floor space for "design excellence," as achieved by invited competition. This, in Dexus's view, demanded both experience and star quality, so Architectus—which had worked on the building's stage-one approval—was invited to team up. Principal Ray Brown Googled "green high-rise architect" and produced the Düsseldorf-based firm Ingenhoven.
The site is a peculiar one, set at the meeting of two conflicting downtown grids—one orthogonal to the harbor front, two blocks north, and the other at 45 degrees. Under city-planning codes, it was subject to an absolute height limit and to street-line build-to requirements mandating a four-to-six-story podium. This urban-design expectation was reinforced by the 150-year-old sandstone buildings—part of Sydney's treasured colonial heritage—that typify the area. And there was the floor-space ratio control, incentivizing "excellence."
Ingenhoven's response to these rules was to flout them—hence the subversion. "Do you know how many city-planning rules this breaks?" Gulliver routinely (and proudly) asks. The answer is several. The result, however, is not the macho Modernist arrogance that the rules are designed to prevent—the hermetic tower, the windswept plaza—but a warm, approachable, feminine-feeling building in a fairly hard-edged bit of town.
Ingenhoven's primary design gesture is the ovoid plan. Busting the build-to rule wide open, it creates leftover space in each of the site's four corners. But these spaces, instead of feeling godforsaken, are used. On the north they constitute a sunny plaza, continuous with the massive, encircling flight of steps. And at the back, on the south, they harbor an outdoor café on one hand and the vehicle entrance on the other. Because the ground floor is all public space, home to a second café and offering a shortcut between streets, the entire plane has an open and welcoming feel.
"For me," says Christoph Ingenhoven, standing in the foyer, "this is what the building is about. It's like a stage set. The building is in the city, and the city is in the building."
But that's not the end of it. The elliptical plan has other benefits too. It preserves the neighbors' views, precluding objections. It increases volume-to-surface-area ratio, minimizing heat transfer and energy use. It decreases wind turbulence, reducing lateral loads, column size, and structural cost and increasing openness—while improving amenities at the street and plaza level and making it possible to have major outdoor spaces partway up the building and at the top.
Of course, an all-glass skin—even a double skin ventilated at each floor like this one—would normally be a heat-gain catastrophe, requiring massive, energy-sucking air-conditioning. So the ventilated cavity also contains automatically adjusted, view-preserving louvers that prevent the sun from ever actually hitting the inner glass skin, minimizing solar gain. This means the high-efficiency chilled-beam air cooling is adequate for much of the floor plate.