Industrialization, population growth, and urbanization are all trends driving the explosive growth of the construction industry. Creating buildings to house people and operate industry, together with building infrastructure to provide public services, requires prodigious quantities of energy and materials. Most of these virgin materials are non-renewable, and resource shortages caused by the development of the built environment are becoming increasingly inevitable. The gradually evolved circular economy (CE) is considered a way to ease the depletion of resources by extending service life, increasing efficiency, and converting waste into resources. However, the circularity of construction materials shows heavy regional distinctness due to the difference in spatial contexts in the geographical sense, resulting in the same CE business models (CEBMs) not being adapted to all regions. To optimize resource loops and formulate effective CEBMs, it is essential to understand the relationship between space and CE in the built environment. This paper reviews existing publications to summarize the research trends, examine how spatial features are reflected in the circularity of materials, and identify connections between spatial and CE clues. We found that the majority of contributors in this interdisciplinary field are from countries with middle to high levels of urbanization. Further, the case analysis details the material dynamics in different spatial contexts and links space and material cycles. The results indicate that the spatial characteristics can indeed influence the circularity of materials through varying resource cycling patterns. By utilizing spatial information wisely can help design locally adapted CEBMs and maximize the value chain of construction materials.
Significant demand for natural resources has arisen with the massive expansion of the cities and the rising population worldwide. The development of the built environment is the largest consumer of resources, consuming approximately 35–45% of materials and contributing 40% of global GHG emissions associated with material use (Hertwich et al. 2020; Mhatre et al. 2021). The ensuing resource exploration and related environmental impacts have intensified. It is estimated that the global consumption of building materials has tripled from 2000 to 2017 and produced 30–40% of the world’s solid waste and nearly 5 Gt CO2 emissions, or 10% of global annual emissions (EMF 2015; Pomponi and Moncaster 2017; Hertwich et al. 2020; López Ruiz et al. 2020; Huang et al. 2020).
The built environment is the physical surroundings created by humans for activities, ranging from personal places to large-scale urban settlements that often include buildings, cultural landscapes, and their supporting infrastructure (Moffatt and Kohler 2008; Hollnagel 2014). Opoku (2015) points out that the built environment is not only the physical environment but also the interaction of people in the local community and their cultural experiences. The physical constituents of which differ significantly from other products in that they are characterized by long lifetimes, numerous stakeholders, and hundreds of components and ancillary materials interacting dynamically in the spatial and temporal dimensions (Hart et al. 2019). The inherent complexity within the built environment is seen as a challenge for sustainable urban transition (Pomponi and Moncaster 2017).
Circular economy (CE) is one of the essential conditions and solutions for fostering and promoting sustainability (Geissdoerfer et al. 2017). The CE is an economic or industrial concept that distinguishes itself from the traditional linear economy of unsustainability. It is often understood as a restorative and regenerative economic model that includes three types of business models (CE business models/CEBMs): (1) those that increase resource efficiency and reduce resource consumption (narrowing); (2) those that promote reuse and extended service life through repair, remanufacture, upgrades and retrofits (slowing); and (3) those that convert waste into resources by recycling materials (closing) (Stahel 2016; Kirchherr et al. 2017; Figge et al. 2018; Geisendorf and Pietrulla 2018; Gallego-Schmid et al. 2020). It is also well known that urban systems often exhibit linear material flows and inefficient use of resources (Huang and Hsu 2003). Turning linear practices into circularity and maximizing the utility and value of resources is becoming a new model for production and consumption to protect the environment, mitigate climate change, and conserve resources (Cheshire 2019; Harris et al. 2021; Zeng et al. 2022). But incorrect policy formulation and thoughtless pursuit of CE strategies can negatively affect (Corvellec et al. 2021). Many voices currently argue that CE lacks any actual consensus on the magnitude of the economic, social, and environmental “win–win-win” benefits (Aguilar-Hernandez et al. 2021) and even leads to more significant environmental impacts, economic unsuccess, and employment losses (Spoerri et al. 2009; Schröder et al. 2020; Blum et al. 2020).
Circularity in the built environment refers to an approximation in terms of the materiality of immobile elements of the built environment, such as buildings and infrastructures, and their dynamics. These elements are predominantly composed of bulk building materials, mainly non-metallic mineral materials (Schiller et al. 2017b; Gontia et al. 2018; Yang et al. 2020). Despite few products are manufactured, purchased, disposed of, and recycled in the same geographic location in today’s global market (Skene 2018), the transportation distances of these bulk building materials are limited compared to other types of products due to their low specific value-added (Schiller et al. 2017a). Therefore, Schiller et al. (2017a) point out that analyses on (also circular) material flow in the built environment should be applied regionally, which also applies to studies of the availability and security of the supply of natural raw materials in the built environment (Schiller et al. 2020). It can be concluded that the regional context or the spatial context in the geographical sense (Scholl et al. 1996), in which the built environment is integrated, has a decisive influence on material flows in general and their circularity in particular.
Space is a central concept in geography that broadly consists of two distinctive interpretations: a fundamental attribute of reality (often used with time) and a counting term that denotes human conceptual constructs borne of individual experience and societal factors (Newell and Cousins 2015; Grossner 2017). Spatiality and space are two frequently confused concepts. In contrast to space, spatiality is spatial practices rather than an exogenously given and absolute coordinate system that refers to the ongoing processes and imaginations of making space/materials, regulating behaviors, and creating experiences (Mayhew 2015; Kobayashi 2017). Space is a more relevant core term than spatiality in discussing the built environment in the physical sense rather than the formation process. The importance of space in the circularity of the built environment has been implicitly mentioned in many studies on spatial structure and land use planning (Remøy et al. 2019; Lanau and Liu 2020; Gallego-Schmid et al. 2020). Additional studies have also provided fragmented evidence on characteristics of spatial distribution patterns in the built environment that impact the circular flow of materials (e.g., residential and housing density) (Condeixa et al. 2017).
Read more on DOI‘s article.
The image above is of ScienceDirect