Air Conditioning the Louisiana State Capitol ✓ Most Recent

The two essential requirements for the development of the North American skyscraper are considered to be the elevator and air conditioning. However, contemporary photographs of skyscrapers in the 1920s show they had opening sash windows indicating that, at least for the upper floors, natural ventilation was used. This is despite air conditioning becoming more common in industrial, commercial and entertainment buildings from the early 1900s onwards.