New York City construction rates are extremely low. It only seems high because high density means you're always close to development, just like you always hear ambulance sirens even though heart attacks aren't more common.
Many Manhattan neighborhoods are classified as historic and don't easily allow tearing down old buildings for new ones. Many buildings in other Manhattan neighborhoods are landmarked and can't easily be improved. And though he upzoned some areas of the city, Bloomberg also downzoned large swaths of outer borough neighborhoods, preventing cheap multi-family home construction (to replace single-family homes). The outer boroughs also suffer from onerous parking minimums, limiting the amount of land used for housing.
De Blasio has been slow in pushing for any sort of upzoning. He's only recently made his first attempt with the relatively conservative East New York rezoning.
Many Manhattan neighborhoods are classified as historic and don't easily allow tearing down old buildings for new ones. Many buildings in other Manhattan neighborhoods are landmarked and can't easily be improved. And though he upzoned some areas of the city, Bloomberg also downzoned large swaths of outer borough neighborhoods, preventing cheap multi-family home construction (to replace single-family homes). The outer boroughs also suffer from onerous parking minimums, limiting the amount of land used for housing.
De Blasio has been slow in pushing for any sort of upzoning. He's only recently made his first attempt with the relatively conservative East New York rezoning.
Some data: http://newyorkyimby.com/2014/08/new-york-citys-is-americas-s...