Barangaroo International Commercial Towers Sydney, Australia

The three Rogers Stirk Harbour + Partners towers are part of the Barangaroo South masterplan which is the Sydney’s largest urban renewal project since the 2000 Olympics. The masterplan unites the Central Business District (CBD) with the waterfront and provides a new financial services hub, creating a vibrant new carbon neutral district in the downtown area. The building of International Towers Sydney has been the driving force behind the Barangaroo project. The towers are conceived as three sibling buildings each with their own identity. Each office tower responds to its unique geographic and environmental condition, along with the changing solar load throughout the day. This response has informed the design development of the floorplate and facades, bringing diversity and individuality to the design of each building. The towers’ design turns convention on its head, creating a workplace for the future. 23,000 office workers will be housed in approximately 300,000m2 of premium office space across the three towers. The flexible 2,500m2 floorplates will enable occupants to personalise and arrange their office spaces according to their unique needs. The acoustic design involved both the shell&core of the office towers and the fit-out throughout the different design phases. Achieving a high performance in terms of waterproofing, energy transmission, acoustics, thermal, and visual comfort, the towers façade was designed with very tight environmental targets. They use fixed external shading to minimise solar glare and load while acting as light shelves for daylight. They are tuned in slope and orientation to maximise view and minimise blind use. For an acoustic stand point the facades were designed to control external noise from the existing environment as well as from the building services located in the adjacent towers. In addition, potential noise generated by the interaction of the wind with the fins part of the external solar shading has been evaluated. Internal sound insulation has been designed to ensure privacy for the users but still maintaining the idea of the buildings as a new district of work and leisure and a sense of community, with 50% open space. Finally, the spaces have been designed dimensionally and in terms of architectural finishes to control reverberance but at the same time maintaining liveness.