I have a confession to make: I am an inveterate science-fiction fan. I particularly enjoy reading the grand masters of the genre from the fifties to the eighties, the likes of Frank Herbert, Philip K. Dick and Isaac Asimov. What fascinates me in these books is the power of prediction of these authors. Many of the descriptions of the future in their stories have become today’s reality, only a few decades later, even though Asimov and others probably didn’t expect them to come to pass so soon. Let’s dive into a similar exercise, albeit at a much smaller scale, and take a peek at what the future likely holds for façades.
It doesn’t take great powers of foresight to see that building envelopes of the future will need to be highly sustainable. This is a trend that has taken the construction industry by storm and is set to stay and spread. Sustainability will likely come in a number of flavours. Firstly, the materials incorporated into the façade will themselves need to be sustainable. Many materials currently used in building envelopes, such as glass, aluminium and steel, are infinitely recyclable. However, their production from raw materials can consume as much as 20 times more energy than producing them from recycled materials. I believe that progressively, these components will increasingly be manufactured from recycled components, possibly even from the building envelope of demolished buildings.
One of the fascinating aspects of peering into the future is that it often brings us right back to the past. After decades in oblivion, vernacular design strategies are likely to make a strong comeback, blended with modern materials and updated construction techniques. Our forefathers had invented ways of dealing with the common issues relating to building envelopes, such as air and water infiltration, harnessing natural daylight, conserving heat, and many more. These had been refined over the centuries, to be promptly forgotten thanks to an abundance of cheap energy from fossil fuels. In times of greater respect for nature and diminishing raw materials, designers are bound to look back at these vernacular approaches to design, further enhancing and modernising them to turn them into future building envelopes.
Light-emitting surface glass with built-in illuminated pattern
Over the past few years, tremendous efforts have been put into developing ever cleverer ways of using the building envelopes for energy generation from sustainable sources. While photovoltaic panels are undoubtedly the most common of these techniques, many others have also been tried or at least conceptualised, including kinetic façades leveraging wind power, bio-façades using photosynthesis to produce natural gas, etc. With the inevitable increasing scarcity of energy from fossil fuels, the use of building façade to generate energy seems inevitable. Already, solar panels for space exploration offer more than twice the efficiency of consumer panels. With increasing demand for ever more efficient panels, research will undoubtedly come up with breakthrough photovoltaic technologies. One of the most exciting possibilities that is starting to emerge is that of transparent PV panels. Absorbing photons in the infrared range, they offer the dual benefit of producing electricity while at the same time reducing the heat gain on the building. Piezoelectric façade, which generate electricity from the minute flexing of their materials from wind, do not exist now, but they could be developed in the future. Façade materials can be developed that harness the kinetic energy of raindrops impacting it. While a single drop encapsulates a minute amount of energy, billions of drops crashing onto the building envelope could generate a significant aggregate amount of electricity. We can also imagine high-efficiency phosphorescent coatings for the façades, which would reduce or eliminate the need for street lighting. The façades would store up solar light energy during the day, and slowly releasing it at night. Countless other creative methods of generating energy from the building envelopes could be developed.
I foresee that building envelopes will increasingly become adaptive, no longer remaining static or requiring active human intervention to adapt to evolving natural conditions, as is currently the case. On overcast days, the would let more daylight in, and dim down on brighter days. Moveable external shades, or blinds built into glazing have been cropping up on buildings over the past few years, but are still the exception rather than the norm. This is possibly due to higher maintenance cost, or perceived difficulties in implementation. Thermochromic, electrochromic and photochromic glazing solutions already exist today, but these are plagued either technical performance problems, or by extremely long return on investment. These issues are bound to be eliminated over time, allowing building envelopes to become perfectly adapted to ambient conditions, minute by minute, every day of the year. On the same topic of adaptive façades, trickle vents in façades could be linked to indoor sensors, and open automatically when CO2 or contaminants exceed certain levels within the building. Similarly, heat exchangers can be built within cladding panels, reducing the need for HVAC ducts and large AHUs. Research is even being focused on new façade materials able to clean or filter the atmosphere free of pollutants. Such technologies are only just starting to emerge, but are currently either a monopoly or prohibitively expensive, and so limited to a few niche projects. With improving technologies and increased demand, I am convinced that they will become commonplace.
Many similarities exist between the façade and the automotive industries. For one, they both make abundant use of metal, glass, polymers and coatings. Another common point is the use of technology and tools and machines that are much the same in both industries. However, the automotive industry is much more advanced in many respects. Therefore, I believe that much can be learned in terms of future directions for the façade by observing the transformative process that the automotive industry has undergone in the past couple of decades. One of the most obvious differences is robotisation. The automobile manufacturing relies heavily on automation of processes at all levels, as a means of increasing productivity and quality, and this happens at all levels of the production processes. I still recall the first factory dedicated to the production of automotive that I visited. My host had to switch on the light as we stepped in. Since there were no workers at all in the production floor, no lights were on, as the robots did not need them. This is a far cry the vast majority of factories processing glass for the construction industry, where manual labour remains omnipresent. For past projects, I confess having had to contact automobile manufacturers or even shipbuilders for the construction of especially complicated building envelope, for which traditional façade fabricators simply did not have appropriate tools, materials or both to deliver the architectural vision. There is hope yet, though, as some façade manufacturers have recently been making the jump, and are now starting to use robots on their curtain wall production floor. I have even come across a precast concrete factory that is designed to be fully automated, from the adjustment of moulds, the bending and placing of reinforcing bars, and the casting and vibrating of concrete. I’m looking forward to seeing similar transformative efforts from other façade material manufacturers and processes, in particular for the spraying of glass fibre reinforced concrete, the quality and consistency of which too often hinge on the skill of the worker.
Other than automating the production process, efforts are also being made in the development of self-installing façades. With skilled labour fast becoming scarce and expensive in developed countries, devising such strategies makes sense. Already, one company in Sweden has patented a curtain wall system with built-in rails that allow panels that have been installed to guide the next panels in place, thereby cutting the required manpower for an installation team from the typical ten to twelve persons to just two. I believe we will see more and more such systems and strategies blossom in coming years, by the sheer necessity to improve installation productivity while reducing the manpower present on site.
AI-enabled algorithms applied to speed analysis of façade performance
Beyond automation alone, entirely new building envelope designs will become possible through the adoption novel materials and construction techniques. Although the 3D printing technique still remains in its infancy as far as its use in the field of construction is concerned, I see it playing a major role in the not-so-distant future, particular in the fabrication of façades. Already, some architects and builders are using oversized 3D printers to construct buildings, including concrete walls, in record time. We are also seeing new generations of printers that are able to use metal as the printing material. Experimental façades have already been designed and installed using printed metals and polymers on a small scale. In time to come, this approach could become the primary method for producing building envelopes.
Another direction that façades are very likely to take is that of connectedness. Pretty much everything nowadays is becoming connected, and façades are unlikely to be left behind. Façades of the future will be controllable right from one’s smartphone, to override automatic adaptive behaviours, for instance, or to pick a colour scheme for night lighting. Information-gathering is fast becoming an obsessive activity. Sensors built into the building envelope and linked to artificial intelligence systems will undoubtedly appear in due time. There is no limit to the information that these could yield, and more importantly how such data would be used. One exciting opportunity would be the ability to extract information on the actual performance of the façade and of the building, which could then in turn be used to optimise that performance, as well as to improve on the design of future building envelopes. Similarly, sensors could detect the state of cleanliness of the façade, and thus prompt the building managers to initiate a cleaning cycle. This could potentially save water by allowing building owners to wash their façades only when necessary, rather than follow a fixed schedule.
In line with connectedness, it seems logical that interactivity will progressively become the norm for building envelopes. We already have means of animating cladding, display onto glass, mesh and other materials, as well as other means of altering the appearance of façades. Once connected to external means of making these adjustments, we have essentially created interactive façades. Indeed, a small number of buildings have been experimenting with such an approach for advertising purposes, as a way to engage with the public, or simply to elicit a response from those involved in the experience. There is still a long way to go to full harness this technology and to make full use of its potential. This is primarily due to the high cost involved. Like with many new technologies, the first proofs of concept are expensive and limited in their capabilities, but one can see the premises of what is yet to come.
While these insights into façades of the future are still a long shot from the ethereal but extremely high-performance force-field windows of Star Trek, I have good hope that these will come to pass within my lifetime.
This interview was published in IGS Magazines Spring 2020 Issue: Read the full Magazine here for more thought-leadership from those spearheading the industry
Author: Mathieu Meur
Mathieu Meur provides strategic and technical leadership as the director of DP Façade, one of the most forward-thinking façade consultancy practices. Through his training as a multi-disciplinary engineer, and subsequent years of experience heading the largest façade consultancy firms in the world, Mathieu has developed extensive knowledge of all types of building envelope systems, their design, aesthetics, engineering, and related codes of practice. Mathieu has worked on numerous major construction projects in Asia, the Middle East and beyond, including Resorts World at Sentosa – a USD$5 billion integrated resort development, Changi Airport Terminal 1 Upgrading, and The Dubai Mall, the largest mall in the world at the time. Passionate about sharing his knowledge and skills with others, he is a frequent speaker at conferences, writes for technical publications, and has been a lecturer since 2002. Mathieu is also a fellow of the Society of Façade Engineering from United Kingdom since 2010. Considering sustainability to be at the heart of the process, Mathieu was the Chairman of the Singapore Green Building Council Taskforce on Cladding & Roofing from 2012 to 2016. Finally, Mathieu is often called upon by regulatory authorities to help craft codes and regulations related to façade works.