Thin Glass Makes Facades Climate-friendly

At glasstec 2026, you will be presenting EnergySkin, a dynamic system for facade refurbishment that works in two ways – against the cold and against overheating. How does this work in practice?

At first glance, it sounds illogical. To combat the cold, we use an active, external wall temperature control system. Our glass module with integrated photovoltaics is designed in such a way that we can significantly reduce the heat flow even at comparatively low surface temperatures. The U-value is variable and can be adjusted. Such thin layer thicknesses would not be achievable with conventional insulation, such as glass wool. Climate change also works in our favour here: heat loss in winter is becoming increasingly less of a concern. Summer overheating is a more pressing issue. A building that has heated up, with thick passive insulation, cools down only slowly at night, even during a heatwave. Depending on the outside air temperature, our system can be actively and dynamically controlled.

That sounds like the perfect solution when it comes to issues such as climate change and the refurbishment of existing buildings. Are you already in contact with manufacturers regarding this?

As a university, we focus on knowledge transfer as well as testing and laboratory work for product development. In all areas, from basic research to industry-oriented applied research, we collaborate with partners from the construction industry. These include manufacturers such as Dobler Metallbau and Flachglas Sachsen. For the EnergySkin project, we have also brought together experts from TH Köln with partners. We hope to be able to support these projects through to implementation as well.

Thin glass has long been one of your key research areas. You are working on geometrically adaptive facades made from laminated glass less than 1 mm thick. How do these structures work, and what are they suitable for?

Think of curved monitors or foldable mobile phones. We use chemically tempered, very thin glass with high strength. We can cold-form laminated glass made from this using an actuator that controls the movement. We will be demonstrating exactly how this works at glass technology live. Practical applications could include frameless, opening glass elements for ventilation and smoke extraction systems, as well as glass shading systems that adjust to the angle of the sun’s rays. With integrated photovoltaics or printed films, glass can also cast deliberate shadows. Glass joints could one day replace the high-maintenance hinges used in facade construction. Here, too, we are working with partners. Priedemann Fassadenberatung provides design proposals, Folienwerk Wolfen supplies the laminated glass and film technology, and Schott supplies the glass. Taupitz is responsible for manufacturing the connections and movable components. In Düsseldorf, we are showcasing a demonstrator that we're already using in the laboratory for testing purposes.

Together with Bollinger Grohmann, you have developed a tool for the life-cycle analysis of glass facades, which is applied very early on in the planning process. How does the app differ from software solutions already available on the market?  

The KonGlas LCA software combines four elements: parametric facade modelling, structural design, dynamic thermal simulation and life cycle analysis (LCA). The tool enables numerous, systematically generated facade variants to be compared and optimised on the basis of several target parameters. In addition to static analyses, the prospective, scenario-based LCA provides realistic results on the impacts of the facade system throughout its entire life cycle. At the same time, the life-cycle impacts of manufacturing scenarios – such as the reuse and remanufacture of glass components – are assessed. Potential for reuse and recycling is identified as early as the initial planning stage. An artificial neural network (ANN) enables the identification of optimised facade variants and relevant design parameters in real time. When all stakeholders know at a very early stage what the consequences of their ideas and proposals will be, this speeds up the decision-making process. We and Bollinger and Grohmann Consulting will be demonstrating the tool at glasstec and look forward to receiving feedback. 

You are also conducting research into facade glazing through which liquid flows. How do you manufacture this glass, and what could it be used for?

Our approach works like water-filled insulating glazing. The water pressure is equalised within the system, meaning we can use thinner glass. We not only make use of glass’s high surface quality, but also employ a conventional gas filling and modern coatings. Imagine standing behind a transparent heat-exchanger facade on a hot day. Because the incident solar radiation is not only reflected by the glass but is also dissipated and utilised by the water filling the panes, you feel very comfortable despite the heat. We prevent overheating, enhance indoor comfort and improve the building’s energy efficiency. The incident solar energy is dissipated in the same way as in a solar thermal collector. Anyone interested is welcome to come to Dresden to try it out.

The water pressure must be enormous – doesn’t the glass in a heat-exchanger facade need to be particularly thick? What specific applications are conceivable?

Just like our colleagues at the Fraunhofer Institute IWM in Freiburg, we are working on designs that use the thinnest possible glass but can still withstand high water pressures in transparent heat-exchanger facades. To maximise material efficiency, rigidity is needed in the right places. Our colleagues in Freiburg are working with glass panes that function similarly to deep-drawn sheet metal. Here in Dresden, we bond two thin glass panes to a 3D-printed polymer structure. This allows us to design freely, direct light and create shade. The thin glass also enables us to create free-form shapes – similar to the flexible mobile phone displays or curved monitor screens mentioned earlier. 

In your opinion, which topics and developments will shape the glass industry in the coming years?

Life-cycle analysis is becoming a mandatory standard. We must ask ourselves what consequences individual design decisions have on a building's environmental performance, and how these can be quickly assessed. The same applies to the impact of future recycling and reuse strategies on the design process. In all of this, it is important that we use the ever-increasing flood of data wisely and efficiently, and do not allow ourselves to be overwhelmed by it.