**1. Introduction**

Housing is a basic need of human beings and a significant part of the infrastructural requirements of any society. The housing sector constitutes about 38% of the construction industry globally [1]. Over the years, concerns about housing have been directed at availability, adequacy, affordability, and sustainability. Housing availability is a major challenge as housing deficit has been ascribed to some major global challenges, especially population growth and urbanization [1, 2]. Already, more than 50% of the world's population currently lives in urban areas with a future projection of approximately 70% by the year 2050 [3]. This growing population will require functional facilities to sustain livelihood of which housing is one of the most prominent.

Responding to the housing deficit effectively will result in high resource extraction and utilization, which are often associated with negative environmental impacts. Hence, mitigating the impact of housing delivery is important in the efforts to provide adequate housing. Hence, emphasis is shifting toward sustainable options in housing delivery. In this respect, life cycle assessment (LCA) has become a widely accepted methodology for estimating the environmental impact of housing provision toward ensuring sustainability [4]. However, the LCA approach has some limitations, especially with respect to its close affinity with the linear materials and energy flow model as against the circular economy model, which has become a preferred option.

In order to promote sustainability through efficient resource utilization, the circular economy (CE) approach has gained ascendancy. CE refers to an economic growth model that prevents environmental degradation by promoting resource efficiency through waste minimization and adoption of regenerative and restorative practices as against end-of-life approach [5]. The concept is, therefore, closely linked to the sustainable development goals SDGs through Target 12.5, which seeks to substantially reduce waste generation through prevention, reduction, recycling, and reuse (3Rs). The circular economy approach when extended to the housing sector seeks to improve sustainability of housing through the use of circular materials, adoption of circular design strategies, reduction of waste in the housing delivery value chain, and adoption of regenerative strategies in housing design and delivery using innovative processes [2].

In the building and construction industry, the design stage has been recognized as the most efficient and effective stage for adopting sustainable practices in which CE strategies can be explored [6, 7]. According to Fatourou-Sipsi and Symeonidou [8], sustainable building design has become necessary with the enormous environmental impact of the building construction and demolition. It has been estimated that CE will result in 4% of economic growth by 2030 in the EU countries [9]. Hence, the EU through the European Green Deal is active in pushing for a more sustainable Europe [10, 11]. However, developing economies in Sub-Saharan Africa, especially Nigeria, are still grappling with the uptake of sustainable buildings. It is, therefore, necessary to fasttrack the uptake, especially in the housing sector through the route of CE adoption.

In Nigeria, housing deficit has been estimated to be up to 20 million [12]. In addition, awareness of circular economy is growing in Nigeria [13]. However, solid waste management practices appear to dominate discourse on circular economy in the Nigerian context [14–16]. Meanwhile, the construction industry is growing with technology adoption remaining rather rudimentary in the housing sector. The construction waste implications associated with low technology adoption in the housing construction sector can be very profound. This presents an opportunity to evaluate the prospects of circular design strategies in the Nigerian housing sector. Hence, relevant literature were deployed to underscore circular strategies applied to the design of housing. Built examples of public housing in Lagos, Nigeria were also evaluated to determine the extent of alignment with circular design and construction principles. Given the push towards sustainable buildings in Nigeria and the gradual ascendance of life cycle assessment studies in the Nigerian built environment, the current paper also makes good effort to align circular design strategies with the LCA framework.
