Valuation of in-situ Building Materials for Resource Recovery

Abstract

The construction industry is among the largest contributors to global raw material consumption and is responsible for 40% of annual greenhouse gas emissions. Recovery of building materials at the end of a building's life, often seen as a common circular approach, can help mitigate the environmental impacts within this sector. However, the feasibility of recovering in-situ building materials is dependent on various technical, operational, financial, environmental, and regulatory factors, making the implementation of resource recovery complex and challenging. The main objective of this research is to develop methodologies that improve the recovery of building materials at end-of-life through assessment of the value of in-situ building materials. At the core of this research, a decision support tool is developed that incorporates the main factors that impact the value of materials embedded in buildings. The tool is designed based on a multi-objective optimization model that estimates optimal end-of-life options for building components. Throughout this research, the tool is applied to various case studies and analyzed through sensitivity analyses. Using the developed tool, a novel methodology is proposed to assess the efficacy of policies focused on deconstruction and building recovery. Following that, the impact of regional factors such as labour costs, material markets, and socioeconomic factors, are assessed on building end-of-life strategies. The findings underscore the necessity of tailored policies and regulations to effectively reduce waste generation within specific regional contexts. Finally, expanding the applicability of the developed tool on future building stocks, a methodology aimed at evaluating circular design and construction strategies on the recovery potential of buildings is provided. This thesis contributes to the development of optimized material recovery processes that result in waste reduction and carbon emission mitigation. Realizing the recovery potential of building materials is a pivotal step towards fostering a more circular construction sector.