Life cycle assessment guideline for energy-efficient buildings and building products
The building sector is a major contributor to annual greenhouse gas emissions in Europe and is responsible for around 35 percent. In order to minimize overall greenhouse gas emissions - including the share contributed by the building sector - in a sustainable manner, it is not only necessary to assess the energy efficiency of buildings and the building products used in the future, but also to assess the entire life cycle. The Life Cycle Assessment (LCA) method is particularly suitable for mapping the environmental impact of buildings and building products systematically and transparently over their entire life cycle. However, the calculation rules and procedures for carrying out an LCA allow a certain leeway for interpretation. To minimize this, the EU research project "EeBGuide" (Operational guidance for Life Cycle Assessment studies of the Energy Efficient Buildings Initiative) was launched. Coordinated by the Fraunhofer Institute for Building Physics IBP, the aim of the project is to ensure that Europe applies standardized and binding rules, thus providing a common basis for working with life cycle assessments.
The British Building Research Establishment (BRE), the French Centre Scientifique et Technique du Bâtiment (CSTB), the Spanish UNESCO Chair for Life Cycle Studies of the Escola Superior de Comerç International (ESCI), the German company thinkstep AG and the Swedish Prof Ch Sjöström Consultancy AB were secured as research partners. Important aspects considered when drawing up the LCA guidelines included a transparent and clearly-defined procedure and the involvement of LCA experts from all over Europe. In several workshops, a panel of experts consisting of scientists and industry representatives developed new approaches to solutions based on international and European standards, norms and manuals. Controversial issues and critical points were also discussed. Even the first draft was subjected to an external review as well as a Europe-wide survey; the comments and remarks collected were incorporated in the final version of the LCA guideline. The end result was an 800-page reference manual, which not only underwent several external quality checks but was also widely available to the public for comment. Applicability was a further aspect considered: based on a series of example projects, different scenarios were played out and the integrated tools tested.
Generating solutions for everyday problems quickly and easily is the key to efficient work. Thanks to the web-based application, life cycle assessments are now more conclusive than before and contain fewer sources of error. The specified documentation templates and the clear definitions for the different levels of detail "Screening", "Simplified” and "Complete" provide ideal support. Above all, the knowledge of the experts from all over Europe in the fields of LCA, certification and EPD was an enrichment for the project. For different planning phases and the associated different background knowledge about the building or building product, EeBGuide defines life cycle phases and materials which must be included in a life cycle assessment. For example, during the design phase of a project, life cycle assessments can still be drawn up despite the fact that information on geometry and the materials used is sometimes lacking or only vague. To sum up, it can be said that the EeBGuide lays the foundation for standardized life cycle assessments in the building industry. In future, life cycle assessments will be calculated and documented on this basis in research projects within the scope of the Energy Efficient Building European Initiative. Consistent life cycle assessments of buildings and building products throughout Europe will enhance quality and enable the use of standardized LCA data. The guideline provides a sound and standardized basis for simplified and complex life cycle assessments of buildings and building products. As a result, ecological aspects can be included in decision-making processes during both early and advanced planning phases.