Resource-saving in buildings through material substitution: A preliminary study of structural dependencies

Around the world, building stocks are the dominant consumers of mineral resources. Mining activities for the supply of construction materials can lead to conflicts in land use. In order to minimize such sources of conflict, we need improved knowledge of material consumption in the built environment. For this, we can make use of material flow analysis (MFA), which in turn requires the determination of material composition indicators (MCIs). Usually, such indicators are defined for a building type. Currently, there is a lack of research on the impact of material substitution on these MCIs as well as studies on the potential for resource-saving that take technical issues into account. This contribution describes a preliminary study on material substitution in six different reference buildings which compare the bill of materials for structures constructed using standard clay bricks vs potential material substitutes such as hollow, lightweight, or autoclaved aerated concrete blocks. The results show that considerable reductions in material consumption can thereby be achieved for certain parts of the considered buildings. In the future, these effects should be incorporated in the MCIs as key variables for an MFA.