ADG facilitated one of the largest building upcycling projects in the world at AMP Capital’s landmark Quay Quarter Tower. Using innovative design principles to reuse and repurpose the existing structural elements, ADG was the only engineer to meet the architectural vision and complex client development brief and exceed the sustainability targets of the build.









project details


Sydney, New South Wales


AMP Capital

Project timeline


lead contact
Matthew Obst

Practice Manager - Melbourne

Key Expertise

The Quay Quarter Tower project comprised the revitalisation of AMP Capital’s 40-level tower into a landmark, 50-level commercial development, through partial demolition of the existing structure and the doubling of each floor towards the northern (harbour) end of the site.

AMP and their Architect 3XN and BVN were frustrated with the lateral stability solution offer by other engineering consultancies and challenged ADG to develop a lower-cost solution that did not obstruct the harbour views from any point of the extended floor plate.

The development posed significant structural challenges in connecting new and existing structures, including:

  • Condition and capacity of the existing structural elements and materials
  • Condition and compliance of the existing structure with modern codes of practice, including fire and service
  • Design and certification of the existing structure for another 50 years’ design life
  • Compatibility between the new section of the building and existing reinforced concrete structural components
  • Impact of doubling the mass of the floor plates on the lateral design of the building bracing system.

ADG’s design solution enabled the elimination of 40-plus levels of large, structural steel bracing from the primary façade and the maximisation of NLA and harbour views for premium, office-grade space.

The solution developed by ADG used world-first design and software analysis techniques to augment the existing core with a new-build core extension to supply the primary lateral support for the new building envelope. At the same time, ADG was able to mitigate project risks and deliver program and budget economics to AMP Capital, thereby altering the project yield to a suitably high level to secure funding and justify construction to shareholders. Guided by the ‘performance solutions’ methodology as permitted by the National Construction Code 2016, ADG successfully determined the contribution of the existing core structure to the overall structure during demolition, as well as its contribution to construction and design life by:

  • Evaluating current performance and element stress
  • Validating by material inspection, testing and statistical modelling of sampling methods
  • Predicting load paths for strength and service performance during staged demolition
  • Simulating of the construction phase using digital twins, including total building movement.

Specific services provided included:

  • Assessment of structural engineering briefs, reports and performance solutions
  • Structural engineering design and documentation of new-build composite floors and atriums
  • Structural design and detailing of the interfaces between new and old construction
  • Movement and tolerances reporting through the demolition and construction phase
  • Timely, accurate and professional advice in relation to structural engineering and safety policies
  • Provision of a detailed testing regime for investigation of the existing structure.

While AMP Capital has considered several structural solutions through the concept phase of the project, ADG Engineers’ design successfully integrated the existing structure into the proposed building design, capturing a greater contribution of the existing structure and eliminating the addition of significant strengthening outside the core zone.

As a result, Quay Quarter Tower retained 66 per cent of the building’s existing columns, beams and slabs, and 95 per cent of its internal walls. Approximately 50% of the building’s resources were reused from the existing building, resulting in a total carbon saving of more than 7,500 tonnes and an estimated economic saving of $130 million.

The value provided has been reflected in the final product, which will be delivered with no exoskeleton to take advantage of the panoramic view of Sydney CBD.

“What’s clever about this approach is that it has saved a lot of time relative to knocking down and rebuilding a new building, and the end project will be a global best-practice office tower. It’s a great design, notwithstanding the design constraint of having to reuse the core, and I think that’s what’s so clever about it.”

- Chris Nunn, Head of Sustainability, Real Estate, AMP Capital
the Team
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