As form often follows function, changes in architecture can often be traced to changes and innovations in technology. The relatively even skyline of 19th-century cities was not a direct result of the limits of structural engineering. Rather, limiting commercial buildings to four or five stories was primarily due to the limits of human comfort in climbing flights of stairs. Of course, that all changed in 1852 when Elisha Otis invented the "safety elevator," which forms the basis of many elevators in use today. Installation of elevators then led to the development of skyscrapers, in which the city of Chicago played an important role. In fact, a selection of Chicago's skyscrapers have been added to the US Tentative List for eventual nomination to the World Heritage List. But while early skyscrapers were designed to provide direct light and ventilation through the use of U-shaped and E-shaped floor plans, for example, and buildings with central courtyards, the invention of air conditioning, the modern form of which was invented in 1902 by Willis Carrier, drasticially affected the look of modern buildings.
How air conditioning shaped modern architecture—and changed our climate
By Patrick Sisson
Curbed – Cities
May 9, 2017