Toward Context-Aware Vertical Urbanism: A Multidimensional Synthesis of Space Efficiency in Functionally and Formally Diverse Tall and Supertall Buildings

This study examines spatial efficiency in high-rise buildings, a critical yet underexplored dimension of their design that directly affects economic viability, environmental performance, and user experience. As urban density intensifies and land values soar, understanding how usable floor area is maximized across varying forms, functions, and regions becomes increasingly significant for architects, engineers, and city planners. The objective of this research is to identify how architectural form, programmatic function, structural system, and regional context interact to influence net-to-gross floor area ratios. This study introduces a novel, data-driven comparative framework by analyzing 166 globally distributed case study towers—one of the most extensive empirical evaluations in this field to date. Drawing on peer-reviewed sources and CTBUH (Council on Tall Buildings and Urban Habitat) classification standards, the methodology combines cross-sectional typological categorization with quantitative spatial performance metrics. Key findings include: (1) Hotel towers exhibit the highest spatial efficiency, averaging 81.2%, due to vertically repetitive room layouts and centralized service cores; (2) Rigid frame structures outperform other systems, achieving net-to-gross ratios 85% through compact core design and minimal lateral intrusion; and (3) Building height correlates negatively with space efficiency, indicating that extreme verticality incurs spatial penalties. These results offer practical guidance for stakeholders by revealing the typologies and structural-logical combinations that deliver the most efficient spatial outcomes. This research contributes to both theoretical discourse and professional practice by framing vertical usability as a product of coordinated design decisions, rather than isolated architectural features.