The completion of New York’s 432 Park Avenue, designed by Rafael Viñoly Architects, brings the world’s total number of "supertalls"—buildings 300 meters (984 feet) or taller—to 100, according to the Council on Tall Buildings and Urban Habitat (CTBUH), an international organization focused on the planning, design, construction, and operation of skyscrapers. That count double from 50 supertalls in 2010, reflecting a rapid rise in the development of skyscrapers, especially in dense urban areas.
CTBUH confirmed 432 Park Avenue’s completion date as Dec. 23, 2015, when the building became partially occupiable. At almost 1,400 feet, it is the world's tallest all-residential building.
Skyscraper construction doesn't seem to be slowing down. More than 100 supertall buildings are scheduled to be completed in the next five to six years. That list includes Saudi Arabia's Jeddah Tower, designed by Adrian Smith + Gordon Gill Architecture, which will, at 1,008 meters (3,307 feet), surpass the Dubai's Burj Khalifa as the world’s tallest building.
But does building so high up come with a downside? The "Skyscraper Index" is a theory developed in 1999 by British economist Andrew Lawrence that explains how overheated economies often plummet following the completion of expensive towers. A recent case study is the inauguration of the Burj Khalifa, designed by Skidmore, Owings & Merrill, while Dubai faced a financial crisis in 2010. Along with construction costs, other challenges in skyscraper development include finding tenants to fill the ample space—an issue with which New York's One World Trade Center struggled when it opened—and maintenance costs and concerns related to the buildings' often unprecedented height. Despite these hurdles, there are also opportunities to advance building technology to facilitate the construction of taller structures, and reduce their environmental impact.
Note: This article has been updated to correct the height of 432 Park Avenue. We regret the error.