James O’Callaghan’s journey as a structural engineer has been unconventional. While formally trained, he quickly developed a deep appreciation for architecture and innovative use of materials, particularly structural glass.
“Transparent structures highlight bad details quite well,” James noted. Good detailing defines architecture. This curiosity about detail, rigor, and materials underpins the company’s practice and his professorship at the Technical University of Delft.
Today, James is deeply engaged in sustainable construction, examining buildings holistically and using efficient structural solutions alongside environmentally friendly materials.
Brave clients make bold buildings
For James, meaningful architectural innovation begins with the client. “Ambitious architecture comes from brave clients,” he emphasized. Many buildings are mediocre because they were driven by clients with different priorities.
This alignment facilitated the ambitious designs of Apple’s trailblazing buildings and the Atlassian Tower project, which aims to reduce embodied carbon by 50%.
Rethinking high-rise efficiency
Eckersley O’Callaghan
Material efficiency involves revisiting foundational design assumptions. “Columns are structurally efficient. Beams and floors are not,” James explained. Sustainability demands a re-evaluation of preferences for open, column-free spaces.
The future of skyscrapers lies in compromise and collaboration, rethinking layout, orientation, and structure for maximum environmental performance.
Lessons from Atlassian Tower
The Atlassian Tower in Sydney exemplifies these principles: Rising to 200 meters, it combines a concrete core, a steel exoskeleton, and interspersed timber floors.
James stated that early collaboration and a visionary client made the project possible. From procurement choices to navigating fire codes, every decision prioritized sustainability.
Can glass be sustainable?
Given James’s legacy in structural glass, I asked about its future amidst tightening energy codes. Although theoretically 100% recyclable, only 5–10% of architectural glass is recycled.
However, there is hope. James and his peers are exploring reuse systems and casting waste glass into new architectural elements. Facade performance expectations are rising more rapidly than glass technology can keep pace. “There is pressure to use less glass, but it remains indispensable,” he contended.
Digital design and the road ahead
Digital design has transformed how Eckersley O’Callaghan approaches projects. Engineering has shifted from an iterative process to a parametric one.
AI and sensor data will increasingly influence engineering. Structural feedback loops could reveal overdesign in structures, leading to material savings.
Coming to Helsinki
At the Nordic Facade Forum 2025, James will provide insights on the evolution of facade technology and its future. From material trends to environmental imperatives, his talk will offer perspectives for designers, engineers, and developers.
Connect with James on LinkedIn and learn more about Eckersley O’Callaghan at www.eocengineers.com.
Visit www.gii.fi to view the full program and register for the event on June 9, 2025.
Nordic Facade Forum
