The architects, Frank J. Helmle and Harvey Wiley Corbett of the firm Helmle & Corbett, gave the Bush Tower a neo-Gothic appearance that was somewhat similar to the nearly contemporary Woolworth Building. The main contractor was the Thompson-Starrett Company, while the terracotta contractor was the South Amboy Terra Cotta Company. Various firms were involved in furnishing the interior. The building measures approximately from ground to roof. The tower is described as being 30 stories tall, or 29 stories if its double-height top story is counted as one floor. Form The Bush Tower was the city's first skyscraper to be constructed following the passage of the 1916 Zoning Resolution. Because the zoning ordinance greatly restricted the massing of buildings, it was characterized by contemporary writers as possibly the last skyscraper to ever be built in New York City. Instead, it came to impact the designs of other skyscrapers with setbacks (see ). Even though several other architects at the time believed that the plans may have been adjusted in response to the 1916 Zoning Resolution, Corbett wrote that the inclusion of setbacks at the Bush Tower was part of the original design, which predated the resolution. The design for the massing was characterized by Fiske Kimball as being like an "arrow". The building's "shaft", which rises to the 22th floor, measures only wide on 42nd Street and deep. At the center of the eastern facade is a recessed light court, which was designed to illuminate the offices at the center of the tower. A similar light court exists on the western side of the shaft. Because of the narrowness of the lot, the light courts take up significant space within the shaft. The 41st Street wing is ten stories tall and contains a light court on its eastern lot line, adjacent to the shaft. A penthouse is atop the roof of the 41st Street wing's 10th story. For the top stories, Corbett wrote that he wanted "an appropriate finish [...] which would give the entire building the appearance of a soaring cathedral tower". Therefore, the top eight stories were designed as a six-story octagonal shaft set back from all sides, with a two-story roof pavilion. A water tower and elevator equipment is hidden behind the mansard roof above the pavilion. According to Corbett, the placement of mechanical equipment in the roof was a new idea for the time; he recalled a