Established by New York City with 1916 and 1961 zoning regulations, the sale of air rights, or transfer of development rights (T.D.R.'s), "have become the reigning currency of the redevelopment realm, major components in the radical vertical transformation of [New York City's] skyline," writes Finn. "With Manhattan’s skyscraper-proof bedrock in finite supply and the city’s fixation on housing and envelope-pushing office buildings on the upswing — and also the impetus behind the proposed rezoning of 70 blocks around Grand Central Terminal called Midtown East — the sky is not only the limit, it’s the solution."
"These days developers don’t just tailor their blueprints to the lot they own: they often annex, for fees that can run into the multimillions, the airspace above and around their property," he explains. "The process, essentially an invisible merger of building lots that tranlates [sic] into taller, heftier towers with increased profitability, is emerging from a minislump dictated by the economy."
“The trading of air rights is more prevalent than it’s ever been before,” said Robert Von Ancken, an air-rights expert and appraiser who is the chairman of Landauer Valuation and Advisory Services, “and it’s why you’re seeing these monster buildings springing up all over town. All of these new supertowers that are changing the look of the city’s horizon, they couldn’t happen without air-rights transfers.”
But the explosive trend in building as high as possible isn't without its hazards. “Is the future of the city going to be this series of 200-story towers with stultified buildings in between?” asks Robert A. Jacobs, a land-use specialist and partner at Belkin Burden Wenig & Goldman. “You wonder how this will affect the street life, the trees. You wonder about urban plazas surrounded by 50-story walls: what would grow there, mushrooms?”