Improving the Sustainability Performance of Building Materials: An Approach from Life Cycle Thinking

Sammanfattning: The construction industry is expected to play a vital role in meeting the global societal challenge of ensuring sustainable development. Due to the increasing importance of the embodied impact of materials, this thesis investigates how the sustainability performance of building materials can be improved. The investigation is conducted by exploring the influence and the relation of the following aspects to the materials: the different dimensions of sustainability (environmental, social and economic); technical requirements (functional performance); and the exposed systems (material-building-regions). Sustainable product development is considered an effective approach for improving building materials' sustainability performance. However, there is a need for further investigation to determine how to better implement it. The thesis aims to understand what kind of information can support the sustainable product development of building materials. To analyze the sustainability performance of building materials, methods with a life cycle perspective are employed. In addition to the life cycle based methods, which reflect the recent developments in the field, investigations are conducted regarding the phase of product development in which existing sustainability assessment methods can be utilized. In the thesis, two types of building materials are analyzed: thermal insulation materials, and green concrete. An investigation at the level of components and buildings is conducted with focus on a case building constructed in Sweden in 2013. The investigation of how different sustainability assessment methods and indicators can support product development is conducted by considering the phases of product development. It is found that few indicators and methods are able to support the early phase of product development and act mainly as proxy information for setting the goal of the developed material. However, various measures are able to support the later phase of product development, especially the production planning step. Furthermore, in the investigated case materials and building, trade-offs are seen between the dimensions under investigation: the material level, the component/building level, the social and environmental pillars of sustainability. The observed trade-offs highlight the importance and value of the product development phase as an effective measure to handle the occurring compromises. Sustainable product development can offer a platform for more holistic sustainability thinking about and realization of the developed building materials. The thesis emphasizes the value of and the role sustainable product development can play in ensuring the sustainable development of the construction industry.