45 Wall Street was the first large-scale, office-to-residential conversion project that took advantage of the Lower Manhattan Plan and new zoning regulations. The 28-story, 493,000-square-foot “wedding cake” building was built in 1959 as the headquarters of Atlantic Insurance Group and designed by Voorhees, Walker, Smith & Smith. Typical of this building type, the floor plates were extremely deep, in some cases close to 100 feet. The zoning regulations helped make the floor plates usable by allowing a certain percentage of the interior spaces to be mechanically ventilated. These interior spaces, without natural light and air, created legal home offices that have separate entrances from the public corridors. The 432 live/work units are unique in that many of the units are 12 feet wide and some as much as 70 feet deep. The units have a loft-like feel and range from 470 to 2,200 square feet with large thermopane windows.