• • •
Interview: When it comes to sustainable building and living, the Vienna Region serves as a role model for many countries. Two experts discuss the foundation of this success, but also address which measures need to be taken to establish green building as a standard in the long run.
Canada-born technical architect Naomi Morishita-Steffen has been living in Munich since early 2019 and was a resident of Vienna from 2007 to 2018. She earned a doctorate and did research at the Institute of Materials Technology, Building Physics and Construction Ecology at the TU Wien. From 2017 to 2018, she taught the International Summer University course "Green.Building.Solutions.", which she has been co-developing since 2014.
Mario Kubista has been working at Wienerberger Österreich GmbH since the turn of the millennium and is the head of product management for walls and fronts. He is responsible for the development and advancement of products, system solutions and services. This includes serving as an expert in relevant standards committees as well as market observation. He keeps track of the application of digitalisation in construction and is a keen supporter of the BIM planning method (Building Information Modelling).
- Buildings take up about 40 percent of the entire energy consumption. What green building measures do you find particularly effective to change that?
Morishita-Steffen: I think that energy conservation in buildings is a very effective way of reaching climate targets. The quality of the building products has a great influence on sustainability. It is very effective to maximize the quality of the building envelope – ideally with renewable raw materials – and therefore minimize the HVACR (heating, ventilation, air conditioning and refrigeration). This is how you reach energy conservation goals. In the next step, you need to study energy consumption in the building and the energy efficiency of individual electronic devices.
Kubista: I generally agree with you, but I would actually state that essentially, sustainability is about preserving the Creation (recommended reading: "Sustainability: A Cultural History" by Ulrich Grober) – leaving the Earth in such a way that coming generations will still be able to live on it. It is not enough to focus on buildings. Apart from the building concept, the mobility concept needs to be taken into consideration. There is no sustainability if green buildings are built in the Waldviertel but the residents regularly commute to Vienna by car.
Morishita-Steffen: Green building is a broad field and includes many different areas. Every country defines green building differently because they have different goals. There is a wide range of strategies and technologies to reach defined green goals. Optimal building energy efficiency is reached by measures such as an airtight and highly insulated building envelope with minimal thermal bridges, threefold glass sheets and highly efficient HVACR. Because the heat passes the building envelope more slowly, you are able to minimise the HVACR. Minimised energy consumption creates the possibility of the building covering its own building energy requirement.
- Have green buildings and environment labels been established in construction and in architecture?
Morishita-Steffen: Apart from the energy performance certificate, green buildings and environment labels have not been sufficiently accepted by architects or the general population. Since 2002, all EU countries have been required to issue energy performance certificates (EPBD, "Energy Performance of Buildings Directive"). However, every country establishes its own guidelines. In Austria, the energy performance certificate is part of the OIB Guideline 6. The energy performance certificate only applies to the energy requirements, however, and not to all the sustainable aspects which need to be considered in the construction of a green building. Generally speaking, house builders and companies are very interested in green buildings. But there are over 100 building certification systems worldwide and currently at least four in Austria. Building products sometimes have additional ecological certificates. This makes it very difficult for everybody involved, from designers to building product manufacturers to house builders, to get an overview. International certifications such as Cradle to Cradle or the Blue Angel can be expensive for manufacturers. At the same time, there are no marketing measures to create stronger identification with the labels. Why should the layman be convinced of certificates if even architects and engineers don't see incentives for them? We need improved education and training programs to introduce these new sustainable methods to the world of architecture and the building industry in order to popularise the certificates.
Kubista: It is cause for concern indeed that everybody knows the consumption data of his car, but has no idea when it comes to a building. We have invested a lot of money into the natureplus building material certificate, and all brick factories have passed the certification test. Nobody buys these products because they have this seal of quality. The only exception is Lower Austria, and this is only because housing subsidies are higher when certified ecological building materials are used. If you use natureplus-certified bricks for the outside wall, there is an additional sustainability subsidy. Apart from these financial incentives, however, few people concern themselves with this. It would be more important that people buy the product because it's sustainable.
- Does that mean that green building is just, so to speak, an ornament of the Austrian education and industry?
Kubista: The Vienna Region is heading in the right direction. There has been a lot of activity in the past ten years. There are more and more universities where sustainability and green building are part of the curriculum. The FH Campus Vienna is currently establishing a Bachelor program in Architecture – Green Building, an architectural course of studies recognised throughout the EU which focuses on sustainable building. Advanced training programs should be kept in mind because the regulations are changing. When I received my training as a construction engineer, all building norms fit into one folder. Today, they fill entire cabinets. It is difficult to get a comprehensive overview. This is also why it is becoming more difficult than it was 40 years ago to establish a universally trained construction engineer or architect.
Morishita-Steffen: Therefore, it is no longer one individual who has all the knowledge of building as a whole, but it is divided into many areas of expertise instead: architects, construction engineers, structural engineers, and so on. Despite the new methods, I think it is essential not to lose the old knowledge. Furthermore, it will be necessary to transfer the needs of the companies to the universities, so that, for example, MA theses with practical applications are possible.
Kubista: This is already happening. We keep close contact with universities and colleges in Austria through constant financing of visiting professorships, support of courses, dissertations and MA theses. For example, there currently is a sponsored two-year software development project for the statical determination of brick buildings in partnership with TU Graz.
- Mr. Kubista, how effective is the Bau.Energie.Umwelt Cluster (BEUC – Building.Energy.Environment Cluster) in advancing the green building scene?
Kubista: The BEUC is a truly bright spot in Lower Austria. Since its reorientation several years ago, it has been focusing on the principal topics of climate, construction and digitalisation in construction. The Cluster is addressing current problems of the building industry, brings companies together in their projects and therefore contributes to finding solutions. Wienerberger has been participating in these projects since 2005. We currently benefit from the Cluster's BIM projects and notice that companies in the building material industry are more and more dependent on each other, are almost forced to cooperate. Today, designers do not work with individual building materials or building products, but increasingly need entire building parts, such as a wall with certain characteristics. This leads to synergies which different industries can benefit from.
- Ms. Morishita, you have over ten years of experience in sustainable building and gathered insight into green building developments in different countries, from Canada to Ireland, Slovakia, Germany and Austria. What are the Vienna Region's advantages?
Morishita-Steffen: I have always been interested in sustainable building. While Canada was lacking in methodology, Austria and Germany have had one for years. I was first introduced to it by reading "Cepheus – Living Comfort without Heating", which documents nine passive houses in Austria, Germany, France, Switzerland and Sweden. Cepheus is an abbreviation of "cost-efficient passive houses as European standards". I later learned that the book was a research report on flagship projects built according to passive house standards. The book was the reason for me to emigrate in 2002, learn German and first study in Frankfurt, then in Vienna. My experiences in different countries tell me that the Vienna Region is far ahead of many countries when it comes to green building. Word gets around. Last year, I was at the World Green Building Council congress "Building Lasting Change" in Toronto, Canada, and presented many best practice examples of the Vienna Region. The feedback was immense, and it turns out that Austria enjoys a reputation as a role model in many areas of sustainability. There are also many interesting approaches in building materials which remained unknown in countries like the US or Canada for a long time, such as aerated concrete. Even regions which have a green building tradition, such as Scandinavia, regularly check the developments in Austria. I came across a book by Robert Schild from Vienna, Habitat Marketing Director of Saint-Gobain Isover, at an Irish construction site: "Isover Multi-Comfort House: Comfort and Energy Efficiency in Buildings". Back then, I was the construction leader in the construction of a sustainable residential building area with 67 apartment houses in Castlelyon, Ireland. I used the book's passive house details as a textbook for our technical details. The residential building area won the Irish Green Award in 2008. In this project, we immensely benefitted from specialised German and Austrian authors such as Robert Schild or Günter Lang, the head of Passivhaus Austria. The BEUC is behind success stories such as the GESA house and the GrünAktivHaus. In my lecture in Toronto, I mentioned clusters as an important structure to facilitate exchanges in technology and knowledge.
Kubista: The brick as a sustainable building material has always been a major subject in the building industry. This is impressively demonstrated by Wilhelminian-style buildings. I can say with a certain degree of pride that the Wienerberger company established itself with the Vienna Ring Road buildings and the residential houses that followed. These sustainable buildings were erected 150 years ago and are still in very good condition. Problems were caused by the two world wars. The economy was weakened, and after the wars, a lot of living space needed to be built quickly with little money. While the residential buildings of "Red Vienna" were trend-setting, the monotonous postwar buildings after World War II only serve as living space and lack the developments of the interwar period.
- What best practice examples represent Austria as a green building nation?
Kubista: Seestadt Aspern is a highlight. We as a brick manufacturer were suppliers to some of the construction sites. Two brick construction projects (construction sites D22 and D23) even received awards from the ASBC and klimaaktiv at the BauZ! congress at the Messe Wien. The secret of the Seestadt's concept is its public transport connection, and this brings me back to my initial statement: green building needs to integrate urbanity and mobility. Cities grow when they are connected to the public transportation system.
Morishita-Steffen: Yes, Seestadt Aspern is an internationally acclaimed green building project which attracts many families. But many small steps still need to be taken to create the ideal infrastructure and high quality of life in order to establish a neighbourhood feeling which has the quality of a real new urban district. There are some noteworthy older projects which show that the Vienna Region started green building projects very early on when the term wasn't as common, such as the residential community Wohnpark Alterlaa. With many open spaces, a mall, short distances, separate garbage collection and so on, they created a small city within the city.
Kubista: Another prestige project is the Biotope City that is currently being built at the Wienerberg, which involves many urbanistic considerations. The size of the buildings, the distances between them and the abundance of green areas can create a microclimate which binds fine dust and makes the summer heat more endurable (the air temperature is up to three degrees below that of the surroundings). We should also mention, even though it's not in the Vienna Region, flagship project 2226 in Lustenau by architect Dietmar Eberle, because it is modelled on the front structure and ceiling heights of the Wilhelminian-style buildings of Vienna and forgoes "smart building" concepts. It proves that "stupid" buildings with extremely reduced HVACR can be sustainable, too, just because of their outside wall construction and a thought-out building geometry.
- What advice can you give to house builders?
Morishita-Steffen: You should take the time to familiarise yourself with the desired architecture and the large range of the latest technologies in the building sector. I think a project is flawed when you heat by electricity without any consideration of energy conservation measures. It's a waste of energy – as if you cut butter with a chainsaw. The design needs to be a symbiosis of good architecture, (building) physics and proper HVACR to offer optimal convenience for the residents. You should fully exploit the physical foundations of regulating by heat, air and moisture transport before introducing mechanical HVACR.
Kubista: For future projects, the design needs to take the entire lifecycle of the building project into consideration, from the initial planning to construction and use to rededication or deconstruction of the building. Only when all steps have been thought-out in a sustainable manner, should you be allowed to build. The BIM planning method offers a sustainable tool in this regard.
Morishita-Steffen: This is why the use of building materials needs to be well-considered, too. Glass, for example, is a material which suggests success and status. If you want to demonstrate that, you live in a building with large glass fronts. But glass fronts are not economical because you need a lot of energy for cooling and/or heating in almost any climate. In this regard, the Boutiquehotel Stadthalle offers a good concept. If a building has more green areas, the surface can absorb more water, and the likelihood of flooding is reduced. But you can also learn from the floor plans of Wilhelminian-style buildings. The rooms can be adapted to many different living conditions without a lot of remodelling. This would reduce waste by a lot. 40 percent of waste on garbage dumps comes from the building industry.
Kubista: To make building materials more efficient, we are constantly doing research to develop our bricks. A brick alone can no longer supply the combination of required heat insulation, noise protection and mechanical stability for multi-story buildings, so we try to combine it with other materials. The integration of mineral insulants in vertically perforated bricks has worked best so far. In Austria, we use hollow bricks and integrated mineral wool pads. There have also been tests with integrated wood fibre, hemp fibre, coconut fibre and sheep wool insulants, but they have been discontinued due to various reasons. Our job is to constantly optimise our product. We intend to serve as a role model across the borders.
The interview was conducted by medienkomplizen / Christian Scherl
Photos: Naomi Morishita-Steffen | Mario Kubista © Wienerberger