The premise of SuPerBuildings project is that it is possible to

- develop a logical structure for the sustainability assessment of buildings considering the environmental, economic and social performance of buildings,
- define sustainability indicators for buildings and to define minimum and advanced performance levels for sustainable buildings,
- define benchmarking criteria for sustainable buildings,
- effectively use sustainability indicators in different stages of the building process, especially in target setting, design, construction and tendering processes, maintenance and building renovation, and thus promote sustainable built environment,
- use sustainability indicators as an instrument of sustainable building steering.

The framework for the assessment of environmental, social and economic performance is being currently developed within CEN and ISO (as outlined in Table B1.1). The project has considered the output of the standardization process and focused on the development of the performance levels and the usability of benchmarking and labeling systems of sustainable buildings.

The starting point of the project was the following:

- The environmental impacts of buildings can be assessed with help of life cycle assessment method. This happens by making an inventory about the land, material and energy resources needed for the production and maintenance of the building and assessing or monitoring the energy consumption that is needed in order to maintain the desired building performance. The assessed quantities of the consumed resources and related emissions can be used as measures of environmental performance and thus as indicators for environmental impacts such as the potential impact on climate change. However, it may be difficult to assess and model the lifetime flows and thus sometimes also such aspects of building performance as durability and service life of building products and flexibility of the building are used as additional parameters that are believed to indicate the use of resources during the building lifecycle. The environmental burdens of a building also depend on its location and access to services. This can also be assessed with help of life cycle assessment by modelling the use of the building and the behaviour of users and assessing the related impacts that come from the use of transportation. However, it is usually found easier to assess the location related environmental impact by using access to services as a measure of performance which indicates the potential environmental impact. Although there is common understanding about indicators and principal assessment methods, full agreement has not been achieved even with such essential methods as assessing primary energy consumption.

- User satisfaction, health and equality of users, productivity and profit describe the social and economic impacts of buildings. Building performance and location affect these impacts. For example, such aspects of location and building performance as access to and availability of services and green areas, affordability, quality of indoor environment, safety and security affect user satisfaction, productivity and profitability. However, the fundamental problem when assessing these impacts is that those are affected not only by building performance and location but also by other issues. For example, productivity only partly depends on building related aspects and user satisfaction may be difficult to distinguish from other aspects of wellbeing. Another fundamental problem is that building performance and location do not unambiguously affect social and economic impacts but through user needs, which vary; the optimum location and the optimal level of building performance depend on the intended use of the building and specific user needs. A specific aspect that lacks common indicators is for example adaptability to climate change. Another problem is that the use of the building may vary during its lifecycle, whereas design is based on assumptions and set default values. Therefore these assumptions may become insufficient. This may have a huge impact on user satisfaction and building performance.

The standardization process as well as recent research projects and initiatives such as UNEPSBCI1 and SUN2 and the Sustainable Building Alliance3 together with the number of EC funded research projects in this domain have created knowledge and common understanding about sustainable building indicators. The project has considered the output of the standardization process and earlier research, developed sustainability indicators and assessment methods for those aspects of sustainability performance of buildings which need further research and focused on the development of the performance levels and the development of the usability of benchmarking and labeling systems in order to promote sustainable building and reinforce its positive impact in Europe.