“Building – with sustainability in mind“
Prof. Dr. Werner Sobek, Stuttgart/GER
In “Population: The First Essay” in 1798, Malthus published his assumptions that exponential population growth would have devastating consequences for humanity. 174 years later the Club of Rome presented its first, well-known report on the “Limits of Growth”. Today, in 2007, in the era of global warming and population explosion, it is hard to understand the rapid increase in the number of SUVs, vehicles that weigh tons and are highly dangerous in accidents, especially those involving children. After decades of refusing to acknowledge in any way the impending problems, are town and city dwellers now preparing themselves for difficult and boggy terrain?
The response to the Club of Rome’s report in terms of global architectural creation was postmodernism, followed by deconstructivism, superdutch, blob architecture and other styles or phenomena like “Berlin architecture”. All of these movements are characterised, on the one hand, by the fact that they completely ignored the imminent environmental problems and, on the other, by the fact that they could never provide an intellectually rigorous answer as to why they were built. At the same time, ecological building approaches that were in keeping with nature and its cycles were associated with architects who had just come down from the higher realms of esotericism. All other opportunities were missed – except for the drafting and implementation of world-leading energy efficiency standards. These standards, drawn up by engineers, environmental experts and the relevant authorities, have not altered the appearance of the built environment, or of architecture. The only changes were increased dimensions for insulating layers, considerably improved thermal insulation values for windows and tighter sealing for the entire building – forced ventilation became a requirement to protect the inhabitants from their own exhalations. It needed a drastic series of warnings in UN reports in 2006 and 2007 – fortunately given an appropriately high profile by the global media – to raise awareness. This positive change in perception was accelerated by the growing recognition in the that current and looming environmental problems can be managed to a previously unforeseen extent – industrially and financially, but also with PR. At the same time however, the required complete conversion of systems and the related investment would necessitate drastic short-term and mediumterm cutbacks in other areas. This raised the question in the as to whether these goals were in fact economically viable and socially worthwhile pursuing, thereby casting doubt on how deep the understanding of the real problems actually is.
The current problems we face can be summed up in three points:
1. Global warming and the accompanying changes are facts. Human action will only influence the scale of them.
2. Global population growth has not slowed down, although the need for this has been known for a long period of time. There are many reasons for this: religious beliefs for one, but also the basic functioning of social safety nets and consequently the stabilisation of whole societies.
3. The majority of the world’s population does not enjoy the prevailing standard of living in the so-called “Western" world. A significant proportion of humankind goes hungry every day. Improving standards of living in many of these countries leads to additional consumption of energy and resources on an unexpected scale. The consequences are drastic price increases and the first resource wars.
It is clear from the above conclusions that an increase in global energy and resource consumption cannot be prevented, at least not in the coming years. This leads us to ask: how can energy be generated whilst conserving resources? How can energy be used more efficiently? How can recycling become the basis of the economy? And how can the energy required for production and transportation be minimised on one hand and waste creation be minimised on the other? How can all emissions be reduced? Against the background of global warming, these questions take on an existential urgency for humanity. Construction could make a contribution of extraordinary significance, which becomes immediately clear from examining a few interrelated facts:
1. In Germany 2003, one third of primary energy consumption was used to heat buildings.6
2. CO2 emissions produced by private households in Germany may have reduced from 129 million tonnes to 122 million tonnes between 1990 and 2003, a reduction of around 5 %, however, as total CO2 emissions decreased from 1,015 million tonnes to 865 million tonnes in this period, the proportion of overall emissions produced by private households in this period actually rose from 13 % to 14 % - despite all the efforts made.8
3. There were 36 million tonnes of waste generated in Baden-Württemberg in 2005. Construction accounted for 26 million tonnes of this total, the equivalent of 72 %. (For comparison, figures from 1996: 45 million tonnes / 37 million tonnes, equivalent to 82 %).3
Whilst significant progress was made in saving energy or energy efficiency in recent years, in particular in Central Europe, more attention needs to be devoted to the questions and problems related to reducing emissions generated in the entire construction process, i.e. including preparatory stages and postprocessing. “Emissions generated” should be taken to mean not just the direct functioning of the building – essentially emissions generated by heating and cooling the building – but also the emissions generated by the building itself, such as plasticizers, particulates or even aromatic compounds.
The construction industry is still only beginning to introduce closed cycle waste management for building materials and components. In particular, there is a need for a comprehensive methodology or training in design and construction for recycling. By indicating that a building is not being built for a short period but instead is built on the assumption that it will stand for several decades, the construction industry has, up until now, preferred not to recognise that even these decades will come to an end. What then remains of a former building is predominantly multi-part building components, from which it is hardly possible to separate the individual materials economically. Anyone who analyses the exterior wall of a completely ordinary residential building will quickly realise that it is made up of 10-20 different materials. From the masonry with its embedded electric cabling and water and gas pipes and their accessories, to the interior plaster, wallpaper, possibly with paint coating, via the external insulation, plaster base and exterior render including its paint coating – all these different materials are almost impossible to separate. Inseparability was always part of the overall scheme of things in construction. The better the building materials were connected to each during the building’s useful life, the better it normally fulfilled its function. After demolition, this advantage of course becomes a disadvantage – there is no other option except to dispose of the parts of the building that can no longer be separated into the original building components. Interestingly, it is precisely the insulating building components that cause the greatest difficulties - unmixed steel-reinforced concrete components can today be separated almost perfectly into the reinforcement and a granulate material that can be reused as concrete aggregate. Steel, aluminium, wood or glass building components, which are typically not used with other materials, similarly present few difficulties.
In the automotive industry, the announcement that car manufacturers would be obliged to pay for the collection of end-of-life vehicles has prompted the development of vehicles that can be constructed and deconstructed easily. This research towards design for recycling can certainly provide inspiration and examples for similar, desperately needed developments in construction. If the foundations for complete recyclability in the built environment were set out, constructors would be within a stone’s throw of formulating goals for the whole industry. This is how we formulate these goals:
1. To build buildings that in terms of their total annual consumption require no energy to operate them when (“Zero energy”)
2. To build buildings that do not produce any harmful emissions ("Zero emissions")
3. To build buildings that are completely recyclable (“Zero waste”)
The call for the three zeros: “Zero energy / zero emissions / zero waste” also form the basis for the "triple zero concept” that is currently being promoted by and the Greater Stuttgart Region in a series of exemplary renovation, new-build and conversion projects (cf the call in 7: "Zero waste, zero emissions, zero carbon footprint”).
Of course, many initiatives of this kind are currently emerging. But to some extent they are uncoordinated, and to some extent they compete against each other. However, the situation such as it is will do no harm, as construction desperately needs impetus and insight from a variety of sources to help it to develop concepts for truly sustainable building. Against this background, the German Federal government's initiatives (such as the “” research initiative and the development of “Guidelines for sustainable building”), as well as initiatives in individual Federal German states, must be judged as positive. Also worthy of praise is the German Sustainable Building Council (GeSBC), founded in June 2007 by scientists, planners, manufacturers of building materials and components, the construction industry, the energy sector, banks and others involved, to a greater or lesser extent, in construction. This charitable association aims to turn legal requirements, political opportunities and sustainable construction goals, worthy of promotion from the point of view of scientific and professional ethics, into an appropriate certification system reflecting the above formulations.
A complete reappraisal of how to make the built environment sustainable is being seen all over the world. Politicians, scientists and the industry are preparing the introduction of sustainability to the built environment. For the most part, its implementation will lie in the hands of architects and engineers, the very people who yesterday had no all-embracing concept for the design and construction of this “sustainable” architecture in its broadest sense – and still have no such concept today. But the scope of the problems and the questions they raise should not be a reason to shy away from them: “It belongs to the signature of humanity, that man is confronted with problems, which are too difficult for man. Man can however not resolve to avoid them because of their difficulty.”.4
If many eco-homes and eco-cars were commercial flops because they all were shaped by a depressive asceticism, then the most important task which product designers, architects and engineers will have to fulfil in the near future will be to make being environmentally friendly breathtakingly beautiful and exciting…5
References
Sobek, Werner: Bauschaffen – auch im Sinn der Nachhaltigkeit. In: archplus 184 (Oct. 2007), page 88
1 Sobek, W.: Nachhaltigkeit und das Bauen in der Zukunft. Deutsche Architekturzeitung DAZ. (July 2002)
2 Sobek, W.: Zum Entwerfen im Leichtbau. In: Bauingenieur 70 (1995)
3 Homepage of the Statistical Office of Baden-Württemberg: www.statistik.baden-wuerttemberg.de
4 Sloterdijk, Peter: Regeln für den Menschenpark. Ein Antwortschreiben zu Heideggers Brief über den Humanismus. Frankfurt: Suhrkamp, 1999.
5 Maak, Niklas: Der grüne Star. Hollywood fährt jetzt im Energiesparauto vor – fährt der Rest der Welt endlich hinterher? in: Frankfurter Allgemeine Sonntagszeitung, 18.02.2007, page 23
6 Homepage der Fraunhofer-Gesellschaft: www.fraunhofer.de
7 Braungart, Michael; McDonough, William: Einfach intelligent produzieren Berlin: bvt Berliner Taschenbuch Verlag, 2005
8 DIW weekly report 9/2005. See also: homepage of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safey: www.bmu.de
