The Empire State Building took 410 days to build. Construction began on March 17, 1930, and the opening ceremony took place on May 1, 1931. The pre-construction work of demolishing the existing building and excavating the site took less than two months.
John J. Raskob, a financial executive for DuPont and General Motors, bought the old Waldorf-Astoria Hotel and had it demolished to prepare a site for the new construction. Architects designed a building with compact center space surrounded by a perimeter of offices whose floor space diminished on the upper floors. All the equipment used in construction was bought new and specifically fitted for the work. As many as 3,400 workers were employed daily. The skeleton of steel girders went up first, followed by the bricks and the interior electrical and plumbing work. All of the work was carefully timed, and much of it took place simultaneously. The 102 floors were serviced by seven banks of elevators installed by the Otis Elevator Company.
Before construction, the cost of the Empire State Building was estimated at $50 million, but due to low wages during the Depression, the total cost came to just under $41 million. New York Mayor Jimmy Walker spoke at the ribbon-cutting ceremony, and President Herbert Hoover pushed a symbolic button at the White House to light the building for the first time.