The unsustainability of building construction
Extensive analyses are not necessary to understand that building construction is fundamentally unsustainable and, as an important sector of the economy, actually fosters and helps to breed injustices.
• The ecological consequences of building have long been visible on the global level. Above all, the long-term effects of buildings and their use on climate, biodiversity and water eco-systems are critical.
• Social injustices arise constantly in the built environment as well, a fact that is particularly highlighted by the vast contrast between the high level of requirements placed on buildings in developed nations and the dire living conditions of the poor all over the world. This is not a marginal phenomenon but a central one.
• Planning and building activities are an important component of the economy and the world of finance. Development in the direction of sustainability is opposed by the striving to maximise profit with minimal restrictions. It therefore faces resistance from powerful economic and financial interests, which are often internationally active.
• What is less evident is the role of the building sector as a factor that normalises unsustainable practices. The established value systems, planning processes and aesthetic preferences of architects and urban designers have all been formed in the fossil age. They frequently stand in the way of necessary innovations and new ideas.
Urban planning and architecture create long-lasting commodities that have (mostly indirect) effects on a cross-regional and even global level. Thus they inevitably relate to the issue of sustainability as a responsibility that extends geographically across borders and over time. Such far-reaching planning decisions cannot solely be considered from the viewpoint of private interest or of the common good of geographically limited communities (e.g. cities, regions or nations). Once this is recognised, justice and its interpretation in relation to sustainability becomes a key question.
What do sustainability certificates achieve?
During the last two decades, a large number of certification systems intended to assess the sustainability of buildings have been created all round the world. To what extent do they integrate a global and cross-generational perspective in building design? Let us consider the DGNB system (i.e. the German Sustainable Building Council) as an example. The DGNB list of criteria covers six areas of action with up to 60 separate criteria, depending on the type of building. Specific indicators, which can be compared by means of a points-based evaluation, are assigned to each of them. In addition, weighting factors are used to incorporate the importance of each criterion in the assessment. Subsequently, the points are added up to produce an overall assessment of the building or area being investigated.
The list of criteria is intended to make the multifaceted concept of sustainability manageable in building design. The assessment enables a comparison between different designs and projects, whereby emphasis is placed on avoiding the creation of insurmountable hurdles. The requirements are therefore established according to what is currently feasible. As a result, the system generates a high degree of acceptance for sustainability considerations in construction and real estate industries and, at the same time, remains compatible with today’s design and building practice.
Criticism of indicator-based certification systems
The large number of criteria in certification systems is often justified by the need to adopt a holistic method. Only in this way — so it is said — is it possible to assess sustainability in all its complexity and with regard to the wide variety of requirements. Such an undertaking, however, is doomed to fail. It will remain impossible to assess even a small, individual aspect of sustainability with all the relevant influencing factors and their interrelationships. The application of holistic methods to future developments is even more futile. For example, it is not possible to predict future knowledge and how it will affect later developments. Sustainability therefore remains a hollow demand without any practical consequences.
All certification systems, including those that purport to be holistic, are based on the selection of specific individual aspects as ‘representatives’ of sustainability. For this to be undertaken properly, selection criteria that are open to scrutiny must be established. Threshold values that indicate the difference between sustainable and non-sustainable must then be specified. Such verification is imperative. As a rule, it cannot be provided directly, but presupposes comparative considerations e.g. in the form of multiple-scenario investigations and their critical evaluation.
The approach outlined above targets sustainability painstakingly with a set of requirements that should be fulfilled independently of one another. In the commonly used certification systems, the so-called benchmark method is used instead. With this method, the requirements specified in laws or standards are defined as medium (= 50 points), whereas the level achieved in current exemplary projects is defined as the target value (= 100 points). According to this definition, a ‘lighthouse’ project that combines today’s best-practice solutions represents the optimum in sustainability. However, simple considerations show that this would be a highly unlikely scenario. What is really sustainable is not determined by current technical possibilities, but by long-term global consequences of planning decisions and building measures.
Ultimately, the combination of individual assessments by means of points and their addition generates further fundamental problems.
• Offsetting indicators against each other with different (even physical) variables.
• Possibilities of compensation between completely alien and therefore non-comparable areas of action.
• Ignoring conflicts of goals within the criteria or between the criteria.
• Definition of certification levels (bronze, silver, gold, platinum) although it appears impossible to justify objective demarcation criteria between them.
At the end of the day, the so-called homogenisation problem is the main point of criticism. The combination of individual criteria in a points system and the subsequent addition of these points do not result in an evaluation of ‘overall sustainability’. Last but not least, the certification process itself results in considerable expenditure of time and money. In the end, these resources are lacking, for the implementation of concrete sustainability projects are separate from the actual building task, i.e. in the global context.
Outline of a new approach
Every criticism should include a counter proposal, which can then be subjected to a review. The aim is not to ‘tighten a few screws’ of the existing certification systems but to ask a more fundamental question: how can the principles of global and cross-generational justice be integrated into a new form of planning practice?
This is by no means a trivial endeavour. Previous conceptions of justice such as developed by philosophers like Immanuel Kant or John Rawls were applicable within clearly defined geographical/political units, especially as far as their contemporaries were concerned. However, there is no agency today that can enforce a globally oriented form of justice. A resolution of this dilemma is mainly provided by models of cooperative justice. The reason for this being that they are not faced with the difficulty of setting out a geographically specific framework for their own applicability. On the contrary, they also enable graduated justice requirements, which can vary according to proximity, affiliation or the urgency of the problematic situation in question.
A new form of design practice based on these models is already visible in many initiatives and projects. It is grounded in the following fundamental considerations:
1) At the moment, it can only be implemented in the form of cooperative partnerships. These have, by necessity, an exemplary character as the implementation of sustainability in real buildings and planning processes is simply impossible in any comprehensive sense.
2) The requirements for building in one’s home country are summarised in a brief list of key criteria that are to be complied with independently of each other (e.g. climate protection, land conservation, socio-economic aspects, use of resources). Where possible, the requirements should be based on long-term scenarios and a risk assessment (e.g. with respect to climate protection and land efficiency). In some cases, however, project-related measures and goals are defined, the effect of which cannot be quantified exactly (e.g. with respect to socio-economic aspects).
3) Every building project triggers one or more social sustainability projects in the global context, over and above the design and realisation. The location and topic chosen are intentionally left open. However, problematic situations that have an effect over the long term should have priority over short-term issues (e.g. immediate assistance in emergency situations). Moreover, direct relevance to the building and planning process is desirable. These partner projects should preferably be financed by means of flat-rate participation (e.g. 0.5 % of the building costs), which is agreed on at the beginning of the planning process and which is binding.
4) The cooperation projects are carried out in the form of social-science experiments. They follow a process of evaluation in order to serve as starting points for future improved projects. In addition to the actual built project, this should also address the design and participation processes, as well as the later use of the building.
Rather than ‘development aid’, the new paradigm involves mutual learning, as the standards of living and building in the developed countries will also be subjected to scrutiny. Honest cooperation and clear experiments, the aim of which is try out small improvements under practical conditions and to learn from mistakes, are essential in this context. Rather than comprehensive sustainability, the far more modest goal should be to deal with concrete tasks and problems and provide justification for a new cooperative practice of sustainability.1)
