Rethinking the Construction Industry Under the Circular Economy: Principles and Case Studies

The research on new ways to make our existing city more sustainable in economic and environmental terms has become a central theme at the national and international levels, with important implications for city management. The collective agenda is focused on retaining, refurbishing and recycling the existing elements by transforming wastes into new resources. This continuous cycle represented by the extension of the product life cycle and the enhancement of the discarded parts in the built environment is changing the economic system used for many centuries. The current linear economy model is going progressively to be converted into a more circular economy. Many sectors—like infrastructure, foods, enterprises, design etc.—are improving their efficiency by adopting a more circular pattern, but construction companies seem to be very far from this purpose. As one of the main sectors responsible of global energy consumption and waste production, the construction industry has to undergo a radical change in perspective on urban development, along with a new social, cultural, and economic interest in rebuilding the existing city in a sustainable way. The aim of this research is to highlight how to transform the construction industry through the circular economy to make urban reuse strategies more sustainable in social, economic and especially environmental terms. The paper considers not only the theoretical implications of the economic paradigm of circularity, but also case studies through which it is possible to evaluate its relevance in terms of design, production and management of such a new perspective. Through a critical analysis of the more relevant circular interventions in Europe to upcycle obsolete buildings, the research highlights the new fundamental rules for the construction industry to regenerate the existing cities. In particular, the cases studies show how the economic and environmental benefits apply to a circular model in the construction industry and how this system is able to generate new social and economic value in existing buildings. The second element is to show how to combine the circular economy with costs via technologies able to match circularity and environmental efficiency.