## 1 Introduction  
The world's population is constantly growing, facing needs for new constructions, which keeps putting enormous stress on our environment and resources. The intensified pressure on resources that are becoming increasingly scarce has largely contributed to inflaming costs overall and creating uncertainty in the short term [1]. The construction industry is responsible for circa 33% of greenhouse gas (GHG) emissions, 40% of waste generation, and 40% of raw material consumption [2, 3]. These figures are results of the linear economic model of \"take-make-dispose\" which has dominated production and consumption patterns for the last decades. In response to the growing environmental crisis and resource scarcity, among other modern-day challenges, the concept of circular economy (CE) has emerged as a new paradigm of innovative practice towards more sustainable economic growth [4]. It aims at making the most of resources and therefore eliminatingwaste, reducing GHG emissions, and addressing resource scarcity. All are achieved by creating value through slow-moving, closed-loop supply chains where resources are reduced, reused, and recycled (the 3 Rs of waste management hierarchy in a CE). The CE has been explored by several scholars (e.g., [5; 6; 7; 8]) and organizations (e.g., the Ellen MacArthur Foundation--EMF [9]) who tried to define the concept with emphasis on different aspects of resource preservation and sustainable development [10]. The Ellen MacArthur Foundation (EMF), through a series of reports [9; 11; 12; 13], explored the CE concept and its ideas. Since 2010, EMF has acted as a collaboration hub for policymakers, market players, and academia to raise awareness and motivate the current generation to employ the CE approach to re-think, re-design, and build a positive future. EMF describes the circular economy as: _\"an industrial system that is restorative or regenerative by intention and design. It replaces the 'end-of-life' concept with restoration, shifts towards the use of renewable energy, eliminates the use of toxic chemicals, which impair reuse, and aims for the elimination of waste through the superior design of materials, products, systems, and, within this, business models\"_[9] (p. 8). In addition to the environmental benefits of implementing the CE model, other social and economic benefits include delivering larger gross domestic product (GDP) values, cutting down material prices [14], creating up to 50,000 jobs [15], and saving 200 billion EUR from primary resources by 2030 [16]. The circular economic model has been gaining momentum in academic research as well as industry and policy plans [5; 9; 10; 17], making its way to the top of international and European political agendas. In this respect, the European Commission (EC) launched the first Circular Economy Action Plan (ECEAP) in 2015, including measures covering the whole lifecycle of products and materials. ECEAP promoted principles of; 1- \"closing the loop\" through intensified reuse and recycling [18], 2- \"slowing the loop\" through preserving products' and materials' values to a maximum extent, and 3- \"narrowing the loop\" through using fewer resources per product. ECEAP held particular promise for achieving multiple Sustainable Development Goals (SDGs), including SDG 6 on energy, SDG 8 on economic growth, SDG 11 on sustainable cities, SDG 12 on sustainable consumption and production, and SDG 13 on climate change. A new Circular Economy Action Plan (CEAP) was adopted in 2020 with more concrete measures to reduce the pressure on natural resources and create sustainable development. Circular economy (CE) action plans entail gradually decoupling economic activity from consuming finite resources and designing resources' second life which target seven priority sectors including \"construction and buildings\" due to their massive share of responsibility in existing environmental crises.