City-roof coupling: Unveiling the spatial configuration and correlations of green roofs and solar roofs in 26 global cities

This study examines the potential of green roofs and solar roofs to contribute to sustainable development in cities. While previous research has focused on individual locations and small-scale studies, this study takes a broader approach by comparing the current state of these roof types in 26 global cities. By analyzing the relationship between city development, functions, morphologies, and rooftop technologies, the study identifies correlations and provides insights into the integration of these strategies. The findings reveal an uneven distribution of these roof types, with concentrations in highly urbanized city centers, indicating disparities in resource allocation and opportunities. The study suggests that cities with higher elevations, greater human development, and social sustainability should consider large-scale deployment of these roofs. Areas characterized by mid-rise and industrial buildings are suitable for both green roofs and solar roofs. Additionally, a comprehensive assessment combining building morphology with demographic, economic, environmental, topographical, and meteorological factors is conducted to determine the most suitable roof technology. The results of this study can guide stakeholders, including governments, property owners, developers, architects, and policymakers, in selecting appropriate roofing technologies that improve indoor conditions, reduce energy costs, address urban challenges, and promote sustainable urban development on a global scale.