Location: Sydney, Australia.

Architect: BVN.

The Greenland Centre in Sydney is a 68-storey apartment building consisting of a new 40-storey tower built on top of an existing 25-storey building. The retention of the existing building, constructed in the 1960s, allowed for an innovative approach to sustainable urban development. The steel frame of the existing building was used as the basis for an enlarged structure, demonstrating that an office building can be converted into an apartment building. The building also provides public performance, recording, and studio spaces for the citizens of Sydney. The architectural composition of the building is revealed by the need to provide external access to apartments in the new tower on its western edge. The solution was to slide the upper tower to the east, enabling all-round access for all the apartments. This was achieved by inserting a large transfer truss between the lower and upper towers. The result is a building that reveals the narrative of a new tower planted upon an existing building, a sustainable outcome that prevented the waste, time, inconvenience, and discarded energy required to demolish the lower tower and build a completely new structure. The upper tower’s lowest floor on level 26 is about the level where it becomes difficult to properly utilize a balcony on a tower. The challenge was to liberate the unused balcony spaces on towers to make them usable as much as possible by countering the strong wind buffering and pressure issues usually associated with tall tower balconies. The engineering design and the architectural design created the “Sydney Verandah” – a space that is defined by a single plate of glass suspended from above and propped out at floor level to spatially create a visually unencumbered glass wall enabling a sense of safe enclosure without the need for a handrail. The result is a space that seamlessly opens the sitting rooms onto the verandah space and connects the interior of the apartment directly to the vastness of the external space without the visual hindrance of a handrail. The majority of the verandahs face north, ensuring that the space will be warmed by the winter sun, and the apartments can effectively be left open to the fresh air all day. By the use of timber floors and soffits, an external room is created that resonates with the characteristics of a truly unique Australian “place” within the ubiquitous international typology of the tall apartment tower. The Greenland Centre is expected to be complete by late 2020.

Photo credit: BVN.