The climate crisis poses a big threat to both our environment and our lives. This has made the reduction of carbon dioxide (CO2) emissions an urgent global necessity.
The built environment is actually responsible for about 42% of annual global CO2 emissions. While building operations are mostly responsible for this, building and infrastructure materials also play a big role here.
This makes it the driving force of climate change, whose negative effects can already be seen in frequent and more damaging weather events.
Thus, we must build not only adaptive facades that have the potential to reduce the need for active heating and cooling, thereby decreasing the energy consumption and environmental impact of buildings but also more resilient architecture that can withstand the challenges presented by climate change.
To build such adaptive facades, architects must utilize design strategies that incorporate the unique local environmental characteristics. This simply translates to prioritizing climate-responsive architecture.
This kind of architecture focuses on designing energy-efficient buildings that are suited to the very climate in which they are constructed. This requires taking into account factors like seasonality, natural shading, rainfall patterns, humidity, etc.
Instead of working against the local climate, climate-responsive buildings work with regional conditions to provide maximum comfort to the occupant while using the least amount of energy possible.
By taking this approach of implementing passive design strategies, towns, and cities can be built to protect them from the increasing frequency and atrocities of the severe weather events that are the result of climate change.
Besides improving the resilience of the buildings by making them better prepared to withstand both weather and natural disasters, climate-responsive architecture offers the benefits of reduced operational costs by making use of natural, passive systems.
Using daylight and natural ventilation instead of systems that use electricity, energy-related operating costs can be significantly brought down. Extensive use of these passive systems has the capability to reduce energy consumption by up to 90%. These passive systems, like natural airflow, even help enhance occupant’s productivity.
By improving energy efficiency, reducing carbon emissions, and protecting natural resources, this architecture also helps facilitate environmental sustainability.
However, climate-responsive buildings also come with the challenge of hefty upfront costs due to the use of sustainable materials and the lengthy and complex construction process. Then there’s the matter of regulatory obstacles.
Sure, the governments are taking initiatives, and regulations around HVAC energy efficiency and thermal insulation have come far, but there’s still a lack of supporting rules for climate-responsive designs. Increasing the adoption of these architectures also requires a focus on education and investment in related expertise.
Despite the challenges, we are seeing a growing interest in such buildings. Some of the core elements of such an adaptive design include utilizing natural sources for airflow and ventilation, a passive solar design that takes the sun’s position into account, naturally sustainable materials like timber and bamboo, and green features on roofs and walls.
Bioinspired weather-responsive adaptive shading
Among climate-responsive architecture, adaptive shading systems are a great way to regulate the interior climate more efficiently by dynamically changing its shape, orientation, or thermal properties in response to external weather conditions.
However, the problem comes with these kinetic shading systems’ reliance on operating energy to activate electro-mechanical devices that drive multiple moving parts. These complex assemblies are vulnerable to malfunctions, which then require costly repairs.
While there are alternatives in the form of passive tinted anti-sun glass, they filter out too much natural light. So, what’s the solution? Well, it’s in nature.
A new study1 by researchers at the Universities of Freiburg and Stuttgart turned to nature and found that there are already solutions for adaptation. They are inspired by biological materials and respond passively to external stimuli.
The solution that researchers took as their model was pine cones, which react to the environment and change their shape despite having completely dead material systems. The pine cone opens and closes in response to changes in temperature and humidity without consuming any metabolic energy.
Using pinecone as a model, researchers developed a new, energy-autonomous facade system that passively adapts to the weather. Termed “Solar Gate,” the system has been installed on the University of Freiburg’s livMatS Biomimetic Shell. livMatS, or ‘Living, Adaptive and Energy-autonomous Materials Systems’ (livMatS), is a research building.
Instead of depending on “elaborate technical devices,” as most attempts at responsiveness in architectural facades do, this research “explores how we can harness the responsiveness of the material itself through advanced computational design and additive manufacturing,” said Professor Achim Menges, head of the Institute for Computational Design and Construction (ICD) at the University of Stuttgart.
According to Menges, who’s also the spokesperson for the Cluster of Excellence Integrative Computational Design and Construction for Architecture (IntCDC), their approach has allowed them to achieve a shading system that autonomously opens and closes in response to weather changes.
This effect is accomplished without employing any mechatronic elements or operational energy. Here, “the biomaterial structure itself is the machine.”
This weather-responsive, adaptive shading system is the first one to operate without electric energy. In addition to bioinspired design, the researchers used natural materials and widely accessible technologies for the “Solar Gate.”
The technology used here was 3D printing, also known as additive manufacturing, which allows for the manufacturing of complex shapes and forms. In this process, three-dimensional objects are created from a digital file by laying down successive layers of material. 3D printing allows for rapid prototyping, customization, cost savings, and high accuracy, in addition to giving design freedom.
The team used standard 3D printers to replicate the direction-dependent structure of cellulose in plant tissues.
Cellulose is the most abundant biomass on Earth. It is also a natural, low-cost, biodegradable, and renewable material that most importantly has inherent hygromorphic characteristics, allowing adapting shading to be sustainable.
This hygromorphic property, which represents the swelling and shrinking with changes in humidity, is frequently observed in nature. The opening and closing of the scales of pine cones is one example of it.
Taking advantage of this property, the team custom-engineered biobased cellulose fibers and then 4D-printed them into a bi-layered structure using pine cone scales as inspiration.
A computational fabrication technique was also developed by the researchers to control the extrusion of cellulosic materials through the FFF 3D printer.
Material systems produced here can autonomously change their shape in response to external stimuli. The cellulosic materials soak up moisture and expand when the humidity is high, causing the elements to curl and open. Meanwhile, in low humidity, these materials release moisture and contract, causing the printed elements to flatten and close.
“Inspired by the hygroscopic movements of the scales of pine cones and the bracts of silver thistle, Solar Gate has succeeded in translating not only the high functionality and robustness of biological models into a bioinspired shading system but also the aesthetics of plant movements.”
– Professor Thomas Speck, livMatS spokesperson and head of the Plant Biomechanics Group Freiburg at the University of Freiburg
The bio-inspired adaptive shading system has already been tested in the real world for its functionality and durability. The team installed it on the south-facing skylight of the livMatS Biomimetic Shell, which assists in the building’s indoor climate regulation.
During the period of more than a year, it was observed that in winter, the shading elements that are 4D-printed open up and allow for natural heating by letting the sunlight in and closed in summer to reduce solar radiation.
The ‘Solar Gate’ is solely powered by weather cycles and does not require any electric energy, representing a resource-efficient and energy-autonomous alternative to traditional shading systems. The bioinspired 4D-printed shading system also offers the advantages of low cost, low material consumption, lightweight construction, and increased operational robustness.
This system, according to the researchers, has much larger implications than just building facades. They wrote that it can also impact broader areas of architecture, engineering, and construction.
In future work, researchers will look deeper into UV-induced degradation and its long-term effects along with the mechanical wear on Solar Gate and quantify the improvement of indoor climate regulation.
Click here to learn how multi-material additive manufacturing paves way for in-house prototyping.
Adaptive Roof Tiles
In the past, we also covered how scientists at the University of California, Santa Barbara, developed adaptive roof tiles. These tiles could cut energy costs in a big way. Their secret is a “radiative switch” that flips between heating and cooling modes, reacting to the temperature outside. The tiles adjust within 3 degrees Celsius of the target. And compared to regular systems, they’re over 2.5 times more efficient. The result is lower bills and less reliance on fossil fuels.
At the core of this innovation is a small, 4-inch square device. It adjusts how much heat it radiates depending on the weather. The goal is to keep indoor temperatures steady—around 65°F (18°C) without the need for constant power. However, this technology isn’t on the market yet, but when it does, it would be able to save energy, cut costs, and help make buildings greener.
Companies
Now, let’s take a look at a couple of public companies that are engaged in adaptive architecture through their focus on innovative solutions for energy efficiency, building sustainability, and material performance.
1. Johnson Controls International (JCI -0.09%)
Johnson Controls offers the largest portfolio of HVAC equipment and controls for more comfortable, healthy, and sustainable building environments. The company’s HVAC solutions can provide measurably clean air and offer total climate control. Its predictive and diagnostic services meanwhile detect structure-related issues before the damage from seismic-related problems occurs. It further offers planned and preventative maintenance and remote building management.
With the race to decarbonization underway, Johnson Controls ensures sustainability through its efficient heating and cooling systems that provide effective climate control along with optimized energy use. The company’s portfolio of HVAC equipment is engineered to maximize energy efficiency.
Besides HVACs, the company also offers an IOT platform, OpenBlue, which enables intelligent and proactive operation and optimization. The platform can process a million data points per minute and aims to make buildings smarter and more efficient.
Johnson Control is also making heavy use of AI in its security solutions for enterprise, commercial, and residential environments. The company has further expanded its AI capabilities in its OpenBlue Enterprise Manager, aiming to take data insights to the next level. These improvements, coupled with equipment upgrades and proactive services, are delivering customers up to 30% reduction in energy spend, up to 20% reduction in maintenance spend, and 10% more optimized space utilization.
“These new AI-driven features not only enhance operational efficiency and sustainability but also empower building owners and operators with unprecedented levels of insight and control. We are committed to pioneering innovations that drive automation and create smarter, more responsive environments for our customers.”
– CTO Vijay Sankaran
As of writing, JCI shares are trading at $82.10, up 4.02% YTD, while having a market capitalization of $54.19 bln. Johnson Controls has an EPS (TTM) of 2.09, while its P/E (TTM) ratio is 39.27. The company pays a dividend yield of 1.80%.
Johnson Controls International plc (JCI -0.09%)
For its last reported quarter, i.e., Q3 2024, Johnson Controls’s revenue fell short of expectations as it came in at $6.25 billion. Its non-GAAP profit of $1.28 per share, however, beat analysts’ consensus estimates by 2.6%. CEO and Chairman George Oliver, at the time, shared that they were “very pleased” with having delivered “double-digit organic sales growth and robust margin expansion.”
According to Statista, Johnson Controls generated global net sales of almost $26.8 billion in the fiscal year of 2023, an increase of almost 6% compared with the previous year.
Most recently, the company acquired Netherlands-headquartered Webeasy, a building automation and controls provider that will align with Johnson Controls’s mission to innovate energy-efficient and sustainable building solutions.
2. Owens Corning (OC +0.11%)
A provider of building and construction materials, Owens Corning has four businesses: roofing, doors, composites, and insulation.
The company’s insulation solutions are for virtually any building situation, covering exterior walls, roofing systems, and HVAC. Its building solutions offer energy and building code compliance, high-level thermal performance, air/water resistance, moisture control, and acoustical performance.
Users prefer the company’s insulation services for their energy efficiency, durability, long-lasting performance, ease of installation, and minimal maintenance.
Owens Corning (OC +0.11%)
As of writing, OC shares are trading at $187.57, up 10.13% YTD, while having a market capitalization of $16.09 bln. Owens Corning has an EPS (TTM) of 11.76, while its P/E (TTM) ratio is 15.96. The company pays a dividend yield of 1.47%.
When it comes to company financials, for the third quarter of 2024, it reported net sales of $3 billion, which was an increase of 23% from the prior year. Its newly acquired doors business contributed over half a billion dollars to this. The company’s delivered diluted EPS was $3.65 and adjusted diluted EPS was $4.38. Free cash flow during this time was $558 million.
Owens Corning returned a total of $252 million to its shareholders through dividends and share repurchases. Talking about its financial strength, Chief Financial Officer Todd Fister said:
“We demonstrated the strong earnings power and cash generation potential of the enterprise. Our team delivered top and bottom-line growth as a result of best-in-class commercial and operational execution.”
When it comes to the company’s sustainability efforts, Owens Corning’s product portfolio helps its customers save energy and lower emissions. During its 2023 sustainability report, Owens Corning had 14 of its products certified as made with 100% renewable electricity and made up a quarter of the company’s total revenue.
The company also reported achieving a 28% reduction in Scope 1 and 2 emissions from a 2018 baseline, moving it closer to its goal of a 50% reduction in GHG emissions by 2030. Progress has also been made by Owens Corning in its efforts to recycle two million tons of shingles per year in the U.S. by the end of this decade.
The construction materials company has also invested in a 52,000-meter square glass mat manufacturing facility to supply the industry with sustainable and stronger building materials.
Conclusion
Global carbon emissions are rising at a rapid pace, causing the Earth’s temperature to rise and lead to extreme weather, increased wildfires, and disruptions to the food supply. With buildings accounting for a considerable proportion of global carbon emissions, it is extremely important that we reduce the energy required for heating, cooling, and ventilation. At the same time, the structures must be capable of withstanding climate disasters.
The answer to both these needs is climate-responsive architecture, which requires paying attention to and incorporating the local climate and geographic characteristics of the region in building designs. Given the high capability of climate-responsive architecture to reduce global carbon emissions in the sector and limit waste production, there is a need for regulatory support and, of course, constant innovation.
Studies like the “Solar Gate” bring promising solutions to the problem that can address the environmental challenges and meet the functional needs of the built environment. They further highlight the potential of accessible technologies such as additive manufacturing and abundant, renewable materials like cellulose in contributing to sustainable architectural solutions.
By embracing natural materials and bioinspired designs and utilizing digital manufacturing techniques, we can build safe, long-lasting structures and a resilient future!
Click here to learn how 3D printing can help tackle prohibitive home ownership in the US.
Study Reference:
1. Cheng, T., Tahouni, Y., Sahin, E. S., Ulrich, K., Lajewski, S., Bonten, C., Wood, D., Rühe, J., Speck, T., & Menges, A. (2024). Weather-responsive adaptive shading through biobased and bioinspired hygromorphic materials. Nature Communications, 15, Article 54808. https://www.nature.com/articles/s41467-024-54808-8
