By adapting to global megatrends and learning from other engineering disciplines, façade engineers can deliver sustainable designs that are human-centred and future-proofed, says Douglas Sum of international engineering, design and advisory company Aurecon.
From a distance, gleaming glass, steel and concrete structures appear invincible and inured from their surroundings, insulating workers and residents from the outside elements and projecting man’s triumph over nature. But as we all know, accelerating climate change and urbanization are increasingly disrupting our industry; and what’s more that disruption is only just beginning.
As engineers, one of the most important parts of our job is to make informed decisions about the future: and not only the coming few years but the next several decades. We must continually ask ourselves questions such as: how does the declining availability of resources impact our designs? Can developers meet consumer expectations without sacrificing sustainability? Are our buildings ready for modern conveniences such as drone deliveries or artificial intelligence? In this article we’ll take a look at some of the global megatrends impacting façade design and ask what we can learn from other engineering specialties.
Scarcity of resources. The world’s resources are diminishing quickly, and we have limited supplies of fuels, water and food. Yet at the same time these are all essential for human survival and maintaining our standard of living. So, what does this mean for façade designers? Of course, we must do more with less, but we also have to maintain (and then improve) the performance of our engineering designs. We need to focus on saving energy, materials, cost and time in our designs, to make sustainability an achievable goal.
The rise of Asia. The money and power of the world is shifting from west to east. China has been the world’s second largest economy since 2010 and we will see further growth from there and the rest of Asia. This means as engineers we need to understand this region, because it is going to play an increasingly important role across the world. We need to understand how to do business with Asia and design products that appeal to the people and companies there. We should aim to replicate the successes and avoid the mistakes seen in other parts of the world.
Volatile weather. Climate change is a reality, and while we won’t immediately halt the climate crisis there are steps we can take to account for it. Extreme weather events are on the rise and our role is increasingly important in protecting people from their adverse effects. Weather events such as typhoons or prolonged high temperatures can have a serious effect on a building’s façade. As engineers we always design for the worst case, but we also need to ask ourselves, “Did I plan for the unplanned?” We must create designs that will tolerate a wider variance in weather.
Demographic shifts. The issue of aging populations is a growing concern for many countries, including well-established economies like Japan and Hong Kong. With tourism now big business we’re seeing a rise in the number of older people traveling, even to the most unexpected locations. From an engineering perspective, our designs for doors and windows must be easy to use and light enough for all ages. Consider especially the trend to “tilt and slide” doors, and oversized doors. While this is driven by the aesthetic value they bring, as engineers we must also guarantee they are practical.
The virtual world. Virtual reality (VR) and augmented reality (AR) are already part of our lives. With advances in entertainment and gaming, it’s likely the homes and offices of the future will incorporate this technology and how that is done will impact façade design. As urbanization increases and populations rise, spaces will shrink and this presents both opportunities and challenges. VR and AR will also facilitate how we present our work, allowing us to demonstrate changes immediately and showing how other options might look — all work at the click of a button.
Consumer expectations. A natural by-product of increasing competition and the advance of technology is how it drives our expectations. Just think of phones, which once we wanted only for their ability to make calls. Today, we expect them to act as multi-function devices. In terms of façades, this new world of instant gratification will have ongoing implications. For example, there is a high likelihood that deliveries via drone will become a reality in the not-too-distant future. But with rising expectations, customers will not only demand we accommodate these within our development, but at multiple points and even across floors.
Look outside the façade
With so much change happening so quickly it can seem overwhelming to try and keep pace with advances in the world. Often it can be difficult to connect what’s happening in the wider society with the work we do as façade engineers, but if we dig below the surface, inevitably we find something relevant to our work. Most often new synergies can be found within other engineering specialties, as our colleagues face the same challenges in their areas of expertise. So, in addition to taking a broad view of the world and incorporating that into our work, I also believe we need to look at what we, as façade engineers, can learn from related disciplines.
Keep on movin’
The first point to note about a building’s façade is that it’s constantly moving. It has to move to be able to do its job, because there’s a lot of movement in the building it surrounds. Structural, wind, seismic or thermal forces will cause buildings to move.To give an idea of the scale, one supertall building I recently worked on in Hong Kong recorded movement of three metres at its top. For some supertall developments under construction we are expecting lateral movement of over 10 metres! How do we engineer a façade to accommodate that?
In a recent case, we took inspiration from the design of footbridges. Under any footbridge there are four bearing pads; one is fixed, one is able to slide in one direction, another can slide in the opposite direction, and one is capable of all movements. For façades we applied the same principles. A good way to think of the movement is to consider a train moving round a bend. Façade sections are always stiff, because they’re typically made from glass or concrete, but with flexible joints in between we can create exteriors capable of moving with the buildings they surround.
Let it flow
For engineers one of the most difficult elements to deal with is water. But one thing we do know is we’ve got to let it flow. Artificial efforts to force water to stop flowing almost always end badly. So, when it comes to façade engineering, we want to prevent the water entering our building, but we also want to let it flow.
In any building façade, there will be two lines of defence. The first is to stop the majority (say 90 per cent) of the water reaching the building. Then we use our second line of façade defence to drain the water out. This provides a perfect solution. The principle of allowing water to flow can be seen in many other areas of engineering, for example infrastructure. Developments must be able to resist water, but equally importantly they must provide somewhere for water to flow.
The issue of fire in façade engineering is one of the most important aspects of our job. Façades can provide a perfect path for the spread of fire, with the air gap between the first and second elements in their design. So, we need to ensure we have a proper fire design with the correct use of firestops.
One of the weakest points in the design is the gap between the floor slab and the curtain wall, so we put a firestop on top of the insulation to prevent the smoke and flames from traveling from floor to floor. For this design practice, which is now used in almost all developments, we have shared the same firestop methodology used in MEP engineering (the pipe penetration between a fire separation wall).
We’re still in the early days of façade engineering so it’s exciting to think what the future holds. Already we can see the importance of client experience in guiding how the industry will develop, especially if we look at what our peers in the world of architecture are doing.
As façades become more complex and important to a building’s design, we will increasingly need to be better at showing our clients what it will look like. For this, we are already building prototypes and models, but as we progress, we’ll use more VR, AutoCAD and 3D printing. With customer experience becoming such an important part of modern-day engineering, designing façades of the future will be about more than just putting on an attractive face.
The future’s bright
These are exciting times to be an engineer. We have the opportunity to create structures that will live for decades and define our environments. Our projects will have a real impact on people’s lives and their perception of the world — there are numerous studies that demonstrate how a building’s design can influence our mood and behaviour in significant ways.
The challenges we face are impossible to ignore but they also present great opportunities and give us a chance to ignite innovations that will propel façade engineering into a new era. These are still relatively early days for our work, but by keeping abreast of shifting trends and tapping into interdisciplinary sectors we can ensure our projects live long into the future.
This article was originally published in IGS Magazines Spring 2020 Issue: Read the full Magazine here for more thought-leadership from those spearheading the industry
Douglas Sum is an Associate and Façade Service Group Leader at Aurecon. Having worked in the Middle East for over 11 years, he is one of the region’s most experienced façade engineers. With over 16 years of global engineering consultancy and contractor experience, Douglas has played major roles in a variety of world-class projects such as Hong Kong Disneyland, Macau City of Dreams, Dubai Metro, Burj Khalifa and The Tower at Dubai Creek.