Transparency Redefined: The Elegance and Sustainability of Glass Facades

By Prof. James O’Callaghan*
FREng CEng BEng FIStructE MHKIE,
Founding Director, Eckersley O’Callaghan

Eckersley O’Callaghan’s journey in glass architecture has been one of evolution, driven by the pursuit of complete transparency. From the early days, our goal has been to realise inventive architectural aesthetics. The focus of our first designs was about transparency, eliminating elements, connections and joints. This is what the industry demanded at that time. Through continuous refinement and the innovative fabrication techniques that were evolving in parallel at a fast pace, we pushed the boundaries of what is possible with glass. A great example showcasing this evolution of glass potential as a structural material is our Apple Fifth Avenue glass cube project.  The production of much larger panels of glass over time led to laminated and tempered panels being achievable up to 18m x 3.6m at the time of construction.

Glass allows for more efficient design of envelopes by combining transparency and its structural capacity with architectural aesthetics. The engineering of glass facades should not only focus on the material itself but also on the elegance and simplicity of its connections, which is of equal importance. Architects have always been driven by the concept of ‘less is more’ and thus as engineers we should strive to find solutions that best achieve this. The answer does not always rely in increasing the amount of glass in the building, but also in reducing or even eliminating the number of fittings, which can often detract from the elegance of the design.

The use of glass is also not limited to envelopes, as we see it being used in other applications, such as glass staircases, which allow to maximise transparency of the space, while reducing the amount of material required.

The chase towards transparency is nowadays in conflict with the energy and the performance of building envelopes. The future of glass lies in its ability to respond to the demands of sustainability. This should not mean that large glass facades will be an item of the past, as glass is paramount for natural daylight, increasing comfort and architectural aesthetics. Consider our Apple Marina Bay Sands project, where glass is not only a cladding element, but an important functional component of the building envelope. Glass was designed to work in harmony with the environment, controlling light and energy transfer to the inside space. It is double glazed and achieves shading through carefully designed ceramic fritting and external louvres. Everything works as a system in an integrated way.

As engineers and architects, it is our responsibility to find innovative ways for glass to maximise its potential while maintaining a sustainable design approach. At Eckersley O’Callaghan, we believe that the true beauty of glass lies not only in its elegance, but also in its ability to shape a more sustainable future.

* James O’Callaghan is a structural and facade engineer with over 20 years of experience. Widely acknowledged as an authority on structural glass, he is perhaps best known for his highly innovative designs for glass envelopes, stairs, bridges and other structural elements in Apple’s iconic retail stores around the world.