The recycled steel skeletons of old buildings are being used to construct a new generation of sustainable high-rise towers

The reliability and versatility of steel has made it indispensable to construction projects all over the world. Since the 19th century, city skylines have been transformed by iconic towers supported by steel frames. But what happens when those towers fall into disuse? A new project in Australia is shining a light on how steel can be used sustainably for future constructions.

In the heart of Sydney’s central business district, the former heritage site that once housed the city’s Water Board office is undergoing a massive refurbishment. The original building’s façade and interior have been fully demolished, but the exposed rigid steel frame is being put to use as the basis for a new construct. When it’s completed next year, The Greenland Centre will become Sydney’s highest residential building, reaching a new height of 235 metres.

“The use of the existing steel frame pays tribute to Sydney’s architectural past, while the ‘Sydney Balconies’ provide an insight into Sydney’s future city living.”

The project is being brought to life by the Shanghai government-owned Greenland Group in collaboration with Probuild, one of Australia’s largest construction companies. The architecture firm BVN was selected from a field of six international architects to design the tower through a City of Sydney Design Excellence Competition.

The goal is to create 470 apartments and six penthouses across 66 floors, while the adjoining art-deco building will also be converted to make space for a creative hub, street-level retail space and a boutique hotel.



Construction on the $400 million refurbishment began in early 2015 and every effort has been made to ensure that the project is in line with the most sustainable construction practices. In total, 99% of all construction waste materials have been recycled, including 25,000 tonnes of concrete and 3,200 tonnes of brick.

One of the greatest challenges for the project is that the original building had only 26 floors. The tower’s original steel frame will be used to support the additional 44 levels that will be built on top of the existing structure, highlighting the enduring strength and adaptability of this material.

The new height of the tower has created further challenges for the construction team, with a modulating angled glass façade added to create a winter garden and provide additional support to the structure. The design will pay homage to the quintessential Queenslander verandahs, or balconies, which are a trademark architectural feature of the region.

Simon Gray, Probuild’s group managing director, said, “the use of the existing steel frame pays tribute to Sydney’s architectural past, while the ‘Sydney Balconies’ provide an insight into Sydney’s future city living.”

The rejuvenation of landmark towers such as the Greenland Centre wouldn’t be possible without the durability and reliability of steel. The skylines of the 21st century will need to be more sustainable than ever before and steel still has a crucial role to play.

As yesterday’s skyscrapers continue to be repurposed for modern needs, many of the materials they’re made of will need to be recycled, but steel will continue to serve as their backbone.


Images: BVN Donovan Hill via CTBUH, iStock