Ecological impact assessment of the «Äerdschëff»-project in Redange/Attert, Luxembourg

Abstract

The Äerdschëff-project in Redange/Attert in Luxembourg is a pilot project for a residential building. It is designed to be self-sufficient in energy, water and, partly, in food production. The realization of this self-sufficiency requires a meticulous design of the building, in order to maximize the use of drinking water and optimize energy production and consumption. Furthermore the building aims to reduce its ecological impact to a minimum and several techniques to achieve this goal are employed- This Master’s Thesis aims to propose methods of assessing the ecological impact of residential buildings on the example of this construction project that focuses on autarky of the finished building, dismantlability and the use of construction materials that have low environmental impact and that are qualifiable as “alternative” materials. After a detailed description of the elements of the Äerdschëff that allow for its self-sufficiency and explain the unconventional approach to designing residential buildings, two different approaches of assessing the environmental impact are proposed: a quantitative approach and a qualitative approach. The proposed quantitative method is based on environmental product declarations of the different used building materials. This offers precise figures of the impact on different categories of the environment and allows for direct comparison to other projects that have been similarly assessed. This method does, however, not allow for assessment of potentially impact reducing methods such as the re-use of drinking water or the implantation of the building in its surroundings. Unfortunately, due to several, important delays, the construction, and planning was, at the time of writing, not at a stage where this method could be applied to the project. The proposed qualitative method is a referential system that offers a more holistic view on a construction project and takes more factors into account than the quantitative method allows for. The referential system used is called LENOZ (“Lëtzebuerger Nohaltegkeets Zertifizéierung fir Wunngebaier” – Luxembourgish certificate for sustainable residential buildings). Whilst this method allows for more factors to be considered, it still is too rigid to grasp the complexity of the studied project. In conclusion, the design of the “Äerdschëff” offers many solutions to the problems of wastefulness in the construction and use of modern residential buildings. It might not be “the” solution, especially considering the substantial land use of the project, but many implemented solutions are applicable to other development projects. None of the of the proposed assessment methods are performant enough to fully consider every aspect of the “Äerdschëff”. The qualitative method, although not ideally contrived, offers a more holistic approach and is therefore better suited to assess residential building projects.