The Chicago School of architecture creates the…

The Chicago School of architecture creates the skyscraper: a result of public amazement at the tall buildings being built in major American cities like Chicago, New York City, Philadelphia, Detroit, and St. Louis.

The term initially refers to buildings with ten to twenty floors in the 1880s.

The building of tall buildings in the 1880s gives the skyscraper its first architectural movement, the Chicago School, which develops what has been called the Commercial Style.

The first steel-frame skyscraper was the Home Insurance Building (originally ten stories with a height of forty-two meters or one hundred and thirty-eight feet) in Chicago, Illinois in 1885.

While its height is not considered very impressive today, it was at that time.

The architect, Major William Le Baron Jenney, created a load-bearing structural frame.

In this building, a steel frame supports the entire weight of the walls, instead of load-bearing walls carrying the weight of the building.

This development leads to the "Chicago skeleton" form of construction.

'In addition to the steel frame, the Home Insurance Building also utilized fireproofing, elevators, and electrical wiring, key elements in most skyscrapers today.

Burnham and Root's 45 meter (148 feet) Rand McNally Building in Chicago, 1889, was the first all-steel framed skyscraper, while Louis Sullivan's 41 meter (135 feet) Wainwright Building in St. Louis, Missouri, 1891, is the first steel-framed building with soaring vertical bands to emphasize the height of the building and is therefore considered to be the first early skyscraper.

One common feature of skyscrapers is having a steel framework that supports curtain walls.

These curtain walls either bear on the framework below or are suspended from the framework above, rather than resting on load-bearing walls of conventional construction.

Some early skyscrapers have a steel frame that enables the construction of load-bearing walls taller than of those made of reinforced concrete.