The architect, structural engineer and president of the Stuttgart Institute of Sustainability talks about whether high-tech and sustainability are compatible
Main picture: Altar for Pope Benedict XVI deployed in Freiburg is a tensile textile structure. Photo © Zooey Braun, Stuttgart
Werner Sobek is one of Germany's leading architects and structural engineers, and president of the Stuttgart Institute of Sustainability. His Stuttgart-based practice has offices as far afield as Moscow, Dubai, São Paolo and New York. As an architect, he expresses modernism clearly in projects such as Haus R128, Stuttgart (2000) and Haus D10, Ulm (2012), but the practice specialises in technological solutions and exploring the possibilities of light-weight materials, realised in structures like the largeoutdoor alter for the previous pope, Benedict XVI, on his 2006 visit to Germany. Sobek has worked with others on numerous large-scale projects, such as the Sony Center, Berlin (2000) and Suvarnabhumi Airport, Bagkok (2006), both with Helmut Jahn. In 2013, as facade consultants, Sobek delivered the extraordinary skin for Zaha Hadid's Heydar Aliyev Center in Baku (see Blueprint issue 332). Current Sobek-designed projects include the Iset Tower, Ekaterinaburg (see Blueprint issue 330).
Blueprint questioned Professor Sobek about technological solutions and sustainability.
BP: Your philosophy and design deliberately embraces a sustainable future that explores and uses technology, as opposed to (in your own words) 'asking how did we use to live and work'. But doesn't this approach fail to recognise the inherent sustainability of low-tech design, for example in the thermal massing of traditional masonry or natural ventilation in many vernacular architectures of warm climates?
Artist Mark Schmitz's 3m-high walk in structure for the Pusan Bienalle, 2004, in Korea, was engineered by Sobek (photo courtesey Werner Sobek)
WS: It's a mistake to assume that high-tech and low-tech are mutually exclusive, or that you can only use the one but not the other. In our projects, we always use a mixture of both. Techniques such as thermal massing and natural ventilation are well established and time-tested. There is no reason not to use them. But in themselves these techniques are not sufficient to satisfy the needs resulting from highly complex building functions and work environments. Already in smaller buildings the inertness of such techniques can prove a problem. In bigger projects they definitely reach their limit.
What we propose is a smart combination of low-tech design with high-tech elements that heighten or improve the user comfort and the building performance even further. Very often these modern elements are fairly simple and straightforward, as in the case of the building automation system we use, alpha.one. This system measures (and helps to regulate) temperature, CO2 concentrations and humidity in the interior. It it self-learning, but does not require any batteries or cables. The system can be installed in less than five minutes. In a way, this is extremely high-tech. But then it is also fairly straightforward, easy to maintain and to exchange, not very cost-intensive - so where's the problem!?
To protect the remains of Station Z, a crematorium at the Nazis' Sachsenhausen concentration camp, the shelter (designed by hg merz of Berlin) is covered with a membrane structure by Werner Sobek. The project was completed in 2005. Photo Zooey Braun
BP: Do not high-tech buildings imply high embedded energy, a long-term need for sophisticated control and maintenance systems, and a built-in obsolescence as technology moves on?
WS: High-tech can make an important contribution to the sustainability of our built environment, significantly increasing the comfort of the users as well as the ecological (and economic performance) of the buildings concerned. In my view, the savings and the increase in comfort thus gained by far outweigh the initial investment that has to be made for high-tech installations.
But, as you state correctly, technology moves on. That's why I call for a flexible approach in the design of our buildings. A typical load-bearing structure (made from reinforced concrete or composites) can last for 100 years or more, without any changes being necessary. The facade may have to be refurbished after 30 years, technical installations already after half that time. Building technology, for its part, may require an overhaul after 5-10 years.
Building design has to take these different life-cycles into consideration in order to allow a finely graduated modernization. It should be possible to renew only those parts of your building that really need it, without disturbing operations in the building for longer than really necessary - there is no reason that the principles of microsurgery should not be transferred to the built environment as well.
By the way: Our buildings need not necessarily be high-tech - unless we talk about high-rise buildings. We have designed many smaller buildings that make do with very little technology. But once you move to a higher level of spatial complexity, you inevitably need more technology in order to maintain comfort and performance at the levels you can (and should) reasonably expect.
One last word on your question whether high-tech necessarily implies high embedded energy. This is definitely not the case. By fare the biggest share of embedded energy is to be found in our building materials, especially in concrete, steel, aluminium etc. The lightweight strategies we employ in our structural design by far outweigh any amount of energy you may have to invest in technological equipment.
The 209m high Iset Tower, Ekaterinaburg Russia, due for completion in 2014 Rendering courtesy Werner Sobek
BP: You have long proposed the concept of cloth/textile as a high-rise skin material. What are the advantages, what about visibility from inside to out, and are any designs emerging?
WS: We still do a lot of research on textile building envelopes. Various projects have been realised successfully, e.g. a fully recycleable altar structure erected for Pope Benedict XVI or a vacuum-stabilised facade at Station Z [a protective structure over the ruins of the Sachshausen crematorium, 2005]. We've proven successfully that and how textiles can be used as facade materials.
As a next step we would now like to implement textiles in the skins of high-rise buildings. This would allow for a radical reduction of the weight of our buildings, drastically reducing the mass of materials used as well as the amount of embedded energy. Moreover, it would also help to cut down on the time needed for construction (and refurbishment). Such building envelopes may not offer the same transparency as a fully glazed facades. But on the one hand there are always sectors where you do not need (or want) transparency - here, textiles with their innate translucency would be the ideal skin material. Building envelopes could thus offer the full range from opaqueness via translucency to full transparency. It's an exciting perspective, and we do hope we will be able to realise one of our designs in the near future!
Interview by Herbert Wright