Design for Disassembly in Mid-Rise Timber Buildings : A Life Cycle and Material Flow Analysis Approach
Olojo, Aduragbemi Deborah (2026)
2026
Master's Programme in Civil Engineering
Rakennetun ympäristön tiedekunta - Faculty of Built Environment
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Hyväksymispäivämäärä
2026-06-08
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:tuni-202606057036
https://urn.fi/URN:NBN:fi:tuni-202606057036
Tiivistelmä
The construction industry is one of the major contributors to resource consumption, construction and demolition waste generation and greenhouse gas emissions worldwide. Although timber buildings are increasingly regarded as a more sustainable alternative to conventional concrete and steel structures, their environmental performance is strongly dependent on how well materials can be recovered and reused at the end of a building’s service life. Design for Disassembly (DfD) is a promising strategy to improve circularity by enabling future material recovery, reuse, and recycling through reversible accessible building assemblies.
This thesis investigates the influence of Design for Disassembly on the circularity and environmental performance of mid-rise timber buildings by using a case study of an eight-storey timber residential building in Finland. A DfD assessment matrix score was developed to evaluate the disassembly potential of timber related floors, walls and roof assemblies based on five criteria (connection reversibility, material purity and layering, component standardization, accessibility and avoidance of wet trades). The assessment results were used to generate DfD-optimized assembly alternatives and remodeled in Autodesk Revit.
The environmental impacts of the optimization were evaluated by Life Cycle Assessment (LCA) using OneClick LCA according to EN 15804 and EN 15978. Material Flow Analysis (MFA) was used to assess the end-of-life (EoL) material recovery routes. Results indicated that as built assemblies had a moderate disassembly potential due to the presence of composite systems, bonded materials, hidden connections, and wet construction methods. The optimization process resulted in better DfD performance in most assemblies using mechanical connections, modular coordination, improved accessibility and dry connection techniques.
The LCA results revealed promising environmental benefits, with the optimized scenario reducing the Global Warming Potential (GWP), Acidification Potential (Ap), and Abiotic Depletion Potential for Fossil resources (ADPF) by around 87%,71% and 23% respectively, compared to the as-built scenario. Moreover, MFA results revealed significant increase in reuse and recycling potential and decrease in landfill disposal dependance. Based on the findings, a simplified DfD impact scorecard to link DfD design quality, material recovery potential and carbon saving performance was developed. The scorecard offers a useful decision support tool to assess the circularity implications of assembly design in the early phases of projects. This thesis concludes that DfD can significantly improve both circularity and environmental performance of timber buildings and offer a framework to support the transition to a circular and resource-efficient built environment.
This thesis investigates the influence of Design for Disassembly on the circularity and environmental performance of mid-rise timber buildings by using a case study of an eight-storey timber residential building in Finland. A DfD assessment matrix score was developed to evaluate the disassembly potential of timber related floors, walls and roof assemblies based on five criteria (connection reversibility, material purity and layering, component standardization, accessibility and avoidance of wet trades). The assessment results were used to generate DfD-optimized assembly alternatives and remodeled in Autodesk Revit.
The environmental impacts of the optimization were evaluated by Life Cycle Assessment (LCA) using OneClick LCA according to EN 15804 and EN 15978. Material Flow Analysis (MFA) was used to assess the end-of-life (EoL) material recovery routes. Results indicated that as built assemblies had a moderate disassembly potential due to the presence of composite systems, bonded materials, hidden connections, and wet construction methods. The optimization process resulted in better DfD performance in most assemblies using mechanical connections, modular coordination, improved accessibility and dry connection techniques.
The LCA results revealed promising environmental benefits, with the optimized scenario reducing the Global Warming Potential (GWP), Acidification Potential (Ap), and Abiotic Depletion Potential for Fossil resources (ADPF) by around 87%,71% and 23% respectively, compared to the as-built scenario. Moreover, MFA results revealed significant increase in reuse and recycling potential and decrease in landfill disposal dependance. Based on the findings, a simplified DfD impact scorecard to link DfD design quality, material recovery potential and carbon saving performance was developed. The scorecard offers a useful decision support tool to assess the circularity implications of assembly design in the early phases of projects. This thesis concludes that DfD can significantly improve both circularity and environmental performance of timber buildings and offer a framework to support the transition to a circular and resource-efficient built environment.