Environmental impact and cost assessment for reusing waste during end-of-life activities on building projects

The construction industry contributes significantly to global environmental loads with massive amounts of construction and demolition waste (CDW) ending up in landfills. To address the need for efficient CDW management, this research proposes a new decision support framework for managing construction waste generated during end-of-life activities for building projects. The framework monetizes potential environmental savings from different recovery options (e.g., reuse, recycle, and so on) and uses multiobjective optimization to determine the optimal quantity of material to undergo each material recovery scenario. The framework uses parametric weights to consider stakeholders' preferences and their appreciation of environmental benefits compared with costs. A case study of a renovation project in Waterloo, Ontario, Canada, is used to demonstrate how the proposed framework can divert concrete and glass waste from the landfill. For this particular project, savings of 200 GJ of embodied energy, 22 m3 of water, and over 12 t of greenhouse gases can be realized from optimal recovery planning using the proposed framework. This study concludes that decision support systems should be used well in advance of end-of-life activities to evaluate trade-offs for recovery planning activities effectively.