Steel Frame Construction

Steel frame construction is a building technique that uses a skeleton frame of vertical steel columns and horizontal steel I-beams, built up in a rectangular grid, to support a building's floors, roof and walls, which are then attached to the frame; the technique made the construction of the skyscraper possible and displaced the earlier iron frame in the early twentieth century. The Bessemer process of 1855 made steel production efficient enough for wide use, and Sidney Gilchrist Thomas solved the problem of phosphorus contamination in steel production in 1879, removing a major barrier to steel's use as a building material, after which mild steel became reliable by around 1880. The Home Insurance Building, completed in Chicago in 1885, was the first structure built with a skeleton frame, though it still relied partly on masonry; the Rand McNally Building of 1890 was the first fully steel-framed building in the United States, and the Royal Insurance Building in Liverpool, designed in 1895 and erected between 1896 and 1903, was the first steel-framed building in the United Kingdom.