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Developable land comes at a premium in high-density alpha world cities such as New York. Soaring property values are threatening historic properties while simultaneously giving developers incentive to push for greater heights. Purchasing what are referred to as "air rights" from a neighbouring land owner allows the building of taller and denser developments that occupy the airspace above abutting lands.
In plain English, air rights are essentially a property's unused development potential. In many cities like New York, small-scale buildings occupying a site with considerable development potential can sign off their air rights to abutting property owners. The transfer of air rights between property owners allows developers on the receiving end to exceed maximum height and density restrictions by adding on the unused potential of their neighbours, evidenced in current New York projects like 432 Park Avenue, Central Park Tower, and One57.
To simplify the concept, imagine two neighbouring sites with 5,000 square-foot footprints on a block zoned to allow 100,000 square-foot developments. One site contains a historically significant low-rise structure while beside it is a vacant lot awaiting redevelopment. The selling of air rights above the historic property to the owner of the empty lot would transfer the historic site's remaining 95,000 square feet of potential to the neighbouring property. This would lead to an almost doubled size of a building occupying the vacant site, up to 195,000 square feet, allowing both property owners to profit from the acquisition while preserving the block's heritage.
While the discussion about zoning air rights has historically been a New York issue, the so-called "Manhattanization" of other major cities around the world has sparked discussion of implementing similar practices elsewhere.
What city do you think would benefit the most from New York-style air rights regulation? Share your thoughts in the comments section below!
