The European Prize for Architecture Awards Tell a friend
GFA above ground: 51.000 m²
Sustainability: 5 Star NABERS Energy Rating, 6 Star Green Star Office Design v2
Architects: ingenhoven associates
Client: DEXUS Property Group
Team: Architectus, Arup, Cundall, Enstruct Group Australia
Photographer: Hans-Georg Esch
The 1 Bligh tower in Sydney’s financial district, highly visible when viewed from the Harbour Bridge, is a prominent addition to the city’s skyline. Australia’s first truly “green” skyscraper is a 139-meter high, 28-story tower. The tower combines the highest grades of sustainability, spatial efficiency, carefully designed integration into the immediate urban environment and boasts a spectacular view of the harbour. Employees in almost all offices can enjoy the panoramic views thanks to the elliptical shape of the building.
The compact elliptical shape is a result of the drive to maximize views and to simultaneously minimize solar heat gains. In terms of urban planning, the building footprint reacts to the special situation around Bent Street where two city grids meet at an angle. The gentle curves of the ground floor naturally connect Bligh Street with the 4 m lower O’Connell Street. The fully public ground floor with public steps visually extends Farrer Place and has become an intensely used seating area. Due to the carefully considered elevation of the office floors, the public steps are well shaded in summer and nicely warmed in winter. A lobby café, an external coffee point, a childcare center, bicycle parking spaces and end-of-trip facilities (lockers and showers) within the “podium” serve tenants and visitors.
The ground floor’s openness continues in the building’s full-height atrium. The atrium allows for views into the office spaces from the glass lifts – as such creating a sense of community between the tenants. Apart from the fully glazed double skin façade, the naturally ventilated atrium is one of the main sustainability features. It serves as a cool air pond and also houses balcony workspaces. The double-layered façades allow for operable external sun blinds that reduce energy demands significantly while maintaining the view of the Harbour.
A “Tri-Generation” system based on natural gas produces cooling, heating and electric power and is twice as efficient as the conventional power grid. In addition, solar thermal collectors on the roof inject high temperature energy into the solar cooling system. A black water recycling system cleans the waste water within the building. To use the plant’s full capacity, additional sewage is “mined” from a city sewer – saving 100,000 liters of fresh water a day.
As a result, the building gained the “6 Star/World Leadership” certification in the Australian Green Star system. It is the first office tower in Sydney to do so. It also gained a “5 Star” rating in the National Australian Built Environment Rating System (NABERS).