The Cadillac Place (formerly the General Motors Building) which served as General Motors headquarters from 1923 to 2001 rises 15 stories to a total height of 220 feet (67 m) with the top floor at 187 feet (57 m). The building has 31 elevators. It was originally constructed with 111,000 m2 and expanded to 129,600 m2. Designated a National Historic Landmark on June 2, 1978 it is an exquisite example of Neo-Classical architecture.
Designed by noted architect Albert Kahn, the structure consists of a two-story base with four parallel 15-story wings connecting to a central perpendicular backbone. Kahn used this design to allow sunlight and natural ventilation to reach each of the building's hundreds of individual offices. The entire building is faced in limestone and is crowned with a two-story Corinthian colonnade. In 1923, it opened as the second largest office building in the world (behind the Equitable Building in New York City).
The base of the building is surrounded by an arched colonnade supported by Ionic columns. The interior features a vaulted arcade with tavernelle, an Italian marble, covering the walls. The arcade was originally lined by stores and an auditorium which could be used for corporate functions or by community groups. The auditorium space was later converted into an auto showroom. On the lower level was a swimming pool which was converted into a cafeteria. Tile with a water-theme gives a hint to the original use of the cafeteria space. A depressed driveway extending between Cass and Second divides the lower level of the main building from the lower level of the Annex.
The entrance is set into a loggia behind three arches of the Grand Boulevard facade. It intersects the arcade to form a large elevator lobby with a coffered ceiling. Floors on the ground level are gray Tennessee marble. On the upper stories, floors are also gray Tennessee marble while corridor walls were originally lined with white Alabama marble.
To the south of the main building is the five-story Annex which served as the original home of General Motors Laboratories. In 1930, the laboratories moved across Milwaukee Avenue to the Argonaut Building and for many years after the Annex housed the Chevrolet Central Office. In 2009 when the Argonaut Building was sold, a fourth-floor pedestrian bridge connecting the two was removed and the Annex facade restored.
Between 2000 and 2002, the building was thoroughly renovated to house the State of Michigan offices, Eric J. Hill participated in the redevelopment which was headed by Albert Kahn and Associates, the original architects. In addition to upgrading existing systems, reconfiguration of some spaces and redecoration, the project installed central air conditioning. When the building was first occupied, it was cooled in the warmer months simply by opening windows. Later, General Motors simply installed window units to cool various offices and work areas. During the renovation, large-scale systems replaced almost 1,900 window units that were left when GM vacated the structure.
After much pressure by the General Motors Board of Directors, William C. Durant agreed in 1919 to construct a permanent headquarters in Detroit for the company he formed in 1908. The corporation purchased the block between Cass and Second on West Grand Boulevard and removed the 48 structures from the site to begin work.
