The Home Insurance Building was a skyscraper in Chicago designed by William Le Baron Jenney in 1884, for the Home Insurance Company in New York. Completed a year later, the building is generally noted as the first tall building to be supported both inside and outside by a fireproof structural steel and metal frame, which included reinforced concrete. The building opened in 1885 and was demolished 46 years later in 1931.
The building was the first tall building to use structural steel in its frame, but the majority of its structure was composed of cast and wrought iron. While the Ditherington Flax Mill was an earlier fireproof-metal-framed building and is sometimes considered to be the first skyscraper, it was only five stories tall. Because of the building's unique architecture and weight-bearing frame, it is considered one of the world's first skyscrapers. It had 10 stories and rose to a height of 138 ft (42.1 m). During its construction, city authorities were so worried that the building would topple over that they halted construction for a period of time so that they could ensure its safety. In 1890, two additional floors were added at the top, bringing the total height to 180 feet (55 meters). In addition to being the first of a new generation of steel-framed skyscrapers built in cities across America and the world, the building set the standard for various other building innovations, including rapid, safe elevators, wind bracing and modern plumbing. In traditional construction, exterior walls, along with interior columns and beams, bore a structure's weight. Additional floors required heavier, thicker walls, resulting in smaller windows and limited natural light--a significant disadvantage before the widespread use of electricity.
To admit the maximum amount of natural light to the Home Insurance Building, architect William Le Baron Jenney used an internal cage of iron and steel to free the exterior from its load-bearing role. The building's outermost iron columns were clad in masonry, but solely to fireproof them. The exterior now could be nothing more than a "curtain wall," made almost exclusively of glass.
Chicago School Architecture Example
The building weighed only one-third as much as a masonry building would have; city officials were so concerned, they halted construction while they investigated its safety. The Home Insurance Building is an example of the Chicago School of Architecture. The building set precedents in skyscraper construction. Jenney's achievement paved the way for the work of a group of architects and engineers that would become known as the Chicago School; together they would develop the modern skyscraper over the last years of the 19th century and the first years of the 20th. Several important members of this group worked at one time in Jenney's office, including Daniel Burnham (who would go on to design New York City's iconic Flatiron Building), John Root and Louis Henri Sullivan. Though New York would later become known for taking skyscrapers to new heights, Chicago has retained its title as the birthplace of the skyscraper, thanks to Jenney and the rest of the Chicago School. The first of these historic buildings, Jenney's Home Insurance Building, was demolished in 1931 to make way for the Field Building (now known as the LaSalle Bank Building).
Buildings without Walls
"...we have no hesitation in stating that the Home Insurance Building was the first high building to utilize as the basic principle of its design the method known as skeleton construction, and that there is convincing evidence that Major Jenney, in solving the particular problems of light and loads appearing in this building, discovered the true application of skeleton construction to the building of high structures and invented and here utilized for the first time its special forms."We are also of the opinion that owing to its priority and its immediate success and renowned the Home Insurance Building was, in fact, the primal influence in the acceptance of skeleton construction; and hence is the true father of the skyscraper."
Report of the Committee Appointed by the Trustees of the Estate of Marshall Field for the Examination of the Structure of the Home Insurance Building, Thomas E. Tallmadge, Chair. 22 November 1931 (Tallmadge, n.p.)