Space Efficiency in Slender Supertall Towers

Space efficiency is one of the most significant planning concerns for creating viable supertall tower projects (≥ 300 m). This issue becomes even more important in slender skyscrapers (aspect ratio ≥ 5). Their small footprint forces service areas and structural elements to be as compact as possible. However, space efficiency in slender supertall towers is a gap in the literature. This critical subject was investigated using data from 68 case study buildings. Findings highlighted the following: (i) Mixed-use, central core, and tapered form were common. (ii) Outriggered frame system and composite had the most widespread use. (iii) Skyscrapers with 71-75% space efficiency and 7-7.9 m aspect ratio were predominant. (iv) Median aspect ratio and median space efficiency of towers were 8.1% and 72%, respectively. (v) Especially in slender buildings with high space efficiency (≥70%), space efficiency changed in direct proportion to aspect ratio. This article will assist architectural and structural designers in the sustainable development of slender supertall towers.