Developing Buildings’ Life Cycle Assessment in Circular Economy-Comparing methods for assessing carbon footprint of reusable components

The buildings’ life cycle assessment is missing consensus on the methods for revealing the environmental benefits in the case of components that are designed for disassembly. To clarify conflicting guidelines, this study provides a new improved method and investigates its applicability by comparing it to two approaches suggested in previous literature. The study investigates the effects of methodological choices by applying them in the life cycle assessment of three buildings with the same spatial layout but different structural solutions: business as usual, wooden structures, and hybrid building with structures designed for disassembly. The method was streamlined by focusing solely on the category of global warming potential and by using table values in life cycle stages that have minor role. The assessment shows that design-for-disassembly could be as powerful climate protection strategy as wooden structures. The main result of this study is the verification of a new secure method for assessing the design-for-disassembly components. The suggested approach would improve the applicability of life cycle assessment in a normative context by improving the consistency of assessment in the case of circular economy. This study suggests further research on combining the utilization rate with buildings’ life cycle assessment to provide even better applicability of the method in circular economy.