Downcycling versus recycling of construction and demolition waste: Combining LCA and LCC to support sustainable policy making

Abstract

Urgent solutions are needed in Europe to deal with construction and demolition waste (CDW). EU policy has contributed to significantly reducing the amount of CDW going to landfill, but most of the effort has been put in downcycling practices. Therefore, further policies are needed to stimulate high-quality recycling of CDW. The present paper presents a combined life cycle assessment (LCA) and life cycle costing (LCC) methodologies to analyse the environmental and the economic drivers in four alternative CDW end-of-life scenarios in the region of Flanders, in Belgium. The four analysed alternatives are (i) landfilling, (ii) downcycling, (iii) advanced recycling and (iv) recycling after selective demolition. LCA results show that landiflling is the scenario having the highest environmental impacts in terms of person equivalent (PE), followed by downcycling and recycling (-36%) and recycling after selective demolition (-59%). The decrease in environmental impacts is mostly due to the avoided landfilling of CDW and the recovery of materials from selective demolition. LCC results indicate that landfilling is the scenario bearing the highest total economic costs. This is due to the high landfill tax in Flanders. The recycling after selective demolition bears the second highest cost. The increase of high-quality CDW recycling can significantly reduce the overall environmental impact of the system. Implementing a high landfill tax, increasing the gate fee to the recycling plant, and boosting the sales price of recycled aggregates are the most effective drivers to facilitate a transition towards a more sustainable CDW management system. The paper demonstrates that the combined LCA and LCC results can highlight the environmental and economic drivers in CDW management. The results of the combined analysis can help policymakers to promote the aspects contributing to sustainability and to limit the ones creating a barrier.

Strategies for Applying the Circular Economy to Prefabricated Buildings

“…In doing so, we discovered that the application of the CE framework on buildings is limited to the use of by-products in concrete production and recycled concrete [3][4][5]. It is important to note that the use of recycled concrete falls outside CE, as recycled concrete and aggregates is a down-cycling of materials; down-cycling is the practice of using recycled material for an application of less value than the original purpose of that material [6]. However, the barriers that stop the CE from being applied to traditional buildings are mainly related to their monolithic nature, architectural aspects that lead to a lack of standard measures, and an underdeveloped closed-loop supply chain.…”

Managerial Areas of Construction and Demolition Waste: A Scientometric Review

“…Application of the LCA method can be classified into six aspects: environmental impacts of a building [ 44 , 99 , 100 ], environmental impacts of construction waste in the construction phase [ 101 , 102 ], environmental impacts of demolition waste in the end-of-life phase [ 103 , 104 ], environmental impacts of demolition waste in the refurbishment phase [ 105 ], environmental impacts of recycled aggregates [ 106 , 107 , 108 , 109 ], and environmental impacts under different CDW management strategies [ 14 , 110 , 111 , 112 , 113 ]. Results show that, compared with landfill, most of waste recycling and reuse methods bring net environmental benefits [ 14 , 101 , 106 , 110 ]. On-site recycling environmental benefits are higher than off-site recycling [ 14 , 104 , 105 , 112 ], and the environmental benefits of off-site recycling are affected by transport distance [ 113 ].…”

Life Cycle Assessment of Prefabricated Geopolymeric Façade Cladding Panels Made from Large Fractions of Recycled Construction and Demolition Waste

“…The construction and demolition sector is one of the biggest consumers of natural resources, which consumes 25% of virgin wood, 17% of fresh water and 40% of all raw materials (e.g., stone, gravel and sand) extracted worldwide, and is responsible for around 40% of all of global greenhouse gas emissions [1,2]. Consequently, it is also one of the biggest waste producers in the world, which annually generates around 35% of all global waste [3]. For example, the construction and demolition sector generates 40% of total urban waste in mainland China, around 30% of total solid waste in the USA and approximately 46% of the total waste in Europe [4,5].…”