Sydney’s first upcycled skyscraper, built almost entirely from salvaged materials, has been named a finalist for the 2025 Earthshot Prize, redefining what sustainable architecture can look like in a circular economy.
Sydney’s Quay Quarter Tower, the world’s first upcycled skyscraper, has been named a finalist for the 2025 Earthshot Prize, the first building ever nominated for Prince William’s prestigious environmental award.
Competing in the Build a Waste-Free World category, the pioneering project demonstrates how reusing existing skyscrapers can replace demolition, slash waste and carbon, and chart a blueprint for sustainable urban growth.
Originally Sydney’s tallest tower when it opened in 1976, Quay Quarter had reached the end of its designed lifespan. Rather than demolish and rebuild, a visionary coalition chose a radical alternative. Danish architects 3XN, working with BVN, engineers BG&E and Arup, and contractor Multiplex, reimagined the tower for the 21st century.
When completed in 2022, the team had retained 65% of the original structure and 98% of the core, avoiding more than 12,000 tonnes of embodied carbon emissions. The result doubled office space from 45,000 to 102,000 square meters and increased capacity from 4,500 to 9,000 people, all while halving the building’s carbon footprint.
The project demonstrates that transformation at significant scale is possible and commercially viable. The first upcycled skyscraper extended the building’s life by decades while redefining what sustainable design can achieve in high-rise architecture.
The buildings sector contributes over 40% of global waste and about a third of greenhouse gas emissions, yet demolition remains standard practice for aging towers. Quay Quarter Tower challenges that norm, showing regeneration can replace destruction without sacrificing economic performance. The success of the first upcycled skyscraper serves as a model for urban resilience and efficiency.
With almost 20% of global buildings needing low-carbon retrofits by 2030, the Sydney landmark offers a replicable roadmap. Its success has already influenced Australian policy and inspired similar projects in London and Singapore.
Managed by Dexus and co-owned by Dexus Wholesale Property Fund, Mirvac Wholesale Office Fund, and Rest, the retrofit’s approach makes it clear that reusing existing structures should become the new default for sustainable cities.
The Earthshot Prize awards five winners £1 million each year to scale environmental solutions, with the 2025 ceremony held on November 5 in Rio de Janeiro, just before Brazil hosts COP30.
Before this nomination, Quay Quarter Tower had already earned multiple honors, including World Building of the Year, the International Highrise Award, and the CTBUH’s World Building of the Year, further cementing its place as a global design icon.
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The transformation involved daunting technical challenges. Converting a 50-year-old structure into a modern, high-performance workplace required precision engineering. The team accomplished the world’s first retrofit of double-deck elevators, typically installed only during initial construction, reinforcing the status of the first upcycled skyscraper as a trailblazer in adaptive reuse.
The retrofit also addressed modern workplace needs, including flexible layouts, natural light, and collaboration zones, creating a contemporary office experience within a reused frame.
Equally critical, the project proved economic feasibility. Developers often assume retrofits cost more than rebuilding, but Quay Quarter Tower demonstrated that sustainability and profitability can align. The first upcycled skyscraper shows that eco-friendly solutions can be financially viable at scale.
By avoiding demolition, the team preserved embodied carbon and reduced material waste while maintaining central Sydney’s architectural heritage. Reusing existing towers can protect city character as well as the climate.
The project now serves as a global case study, with detailed documentation on techniques, cost structures, and performance outcomes freely shared to accelerate industry change. Its success proves that even half-century-old skyscrapers can be reborn, a revelation that could prevent immense waste and emissions worldwide.
Winners of the 2025 Earthshot Prize will be announced in Rio, where the event’s Earthshot Week will unite global leaders, innovators, and investors to scale solutions capable of repairing the planet. The Quay Quarter Tower highlights how the first upcycled skyscraper approach can inspire cities worldwide to prioritize sustainable reuse and circular design.
