I would check two places - First check the The New York City Landmarks Preservation Commission of the City of New York. Certain areas are not allowed to build up past a certain height. For example: SoHo and the Parts of the West Village only allow for buildings to be built up to 3 to 6 stories. If you want to dig deeper, I would suggest looking at the FAR (Floor Area Ratio) of a specific building. FAR tells how high building can be built. This information can be found at the DOB.