The environmental impact of the construction sector can be improved in various life cycle phases of buildings. With the reductions in the operating phase, the potential of the building fabric is moving more into focus. A building that cannot be reused or repurposed as such ties up valuable materials that, if utilised, can replace primary raw materials and the environmental impact for new production. In Germany alone, around 28 billion tonnes of material are tied up in construction and consumer goods, with mineral fractions accounting for the largest share. The intrinsic value and potential uses of materials from demolition vary and depend on material properties, the size of the material stream, purity of type during demolition, available reprocessing routes and the possibility of substitution, i.e. products that can use recycled raw materials. The NuMaRü project aimed to develop an evaluation approach that can assess the potential of different recycling routes (i.e. the possible route from demolition to a secondary product) before demolition. The basis for the method was an evaluation of the literature on the state of the art for the topics of dismantling and reprocessing as well as on various ecological and economic assessment and balancing approaches. Based on the findings of the literature research, a case study was modelled in which a life cycle assessment and parallel life cycle costing were carried out. The literature research findings and the case study served as the basis for developing the methodology. The findings from the literature were categorised into the scale levels of infrastructure, object, construction, and material in order to develop various conclusions about the utilisation paths. These provide the framework conditions for the modelling.

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