Like such other world capitals as London or Shanghai, New York City has been witnessing a disturbing boom in supertall skyscrapers. These extremely tall residential and office towers have been made possible by new technical developments. For example, residential construction benefits from high early-stage strength of high-performance reinforced concrete and pumpability coupled with slip and climb formwork, which saves money by reducing the construction time considerably. Where taller buildings used to be confined to commercial and financial sectors of the city, a new generation of supertall luxury apartment buildings have begun to infiltrate low and mid-rise residential areas. Several such towers now line West 57th Street in Manhattan, giving spectacular views of Central Park from the top apartments. 

They can easily shoot up above their surroundings because the floor area ratio (FAR) zoning regulations do not necessarily limit height. Now with the ability to build higher with such ease, luxury apartments are being planned with ceilings that are twice the height of conventional standard apartments: a new 30-story apartment building today could be the equivalent height of a 60 story, older neighbor with the same allowable floor area, but much lower ceiling heights. Many of these new supertalls contain only one or two units per floor. None of them, of course, include affordable housing.