Design for Disassembly and Reuse : Developing an Indicator System for Volumetric Timber Structures Based on Case Studies

Abstract: The environmental impacts of the construction industry, and the built environment, as the end product of construction activity, are massive due to the extensive use of energy and resources. Sustainability and circular economy are recognized as the main solution to the existing environmental impacts of this industry and the main approach to the sustainable development of it. The transition of a construction project’s life cycle from a linear one starting with material processing and ending up at demolition stage to a real cyclic life cycle needs defining alternative end-of-life scenarios. Deconstruction as one of the alternative end-of-life scenarios is defined as salvaging material of a dismantled structure for reuse or recycling. Design for deconstruction refers to the importance of considering deconstruction as the end-of-life scenario in the design stage of structures. This thesis aims to define the existing challenges and opportunities in the deconstruction of timber structures by the study of cases in which dis- and re-assembly are done. The study also aims to measure deconstructability by developing an indicator system for design for deconstruction of volumetric timber structures based on design for disassembly principles existing in ISO 20887:2020 and the practical principles of the case studies. This is done by interviewing people at five different companies who were engaged in the dis- and re-assembly of structures. The study of these cases shows the gap between disassembly principles and real-world experience from a learn-from-practice point of view. The developed tool as the indicator system is consisted of 25 indicators under seven principles and is able to measure and provide a deconstructability grade of structures out of 100 for each principle and a total deconstructability grade based on all principles.