The introduction of steel to architecture has resulted in stronger, taller, and longer-lasting buildings. It has also seen a significant reduction in the materials required to construct buildings. Arguably, the Ditherington Flax Mill, built in 1797, was the first building to be recognised as being a fully integrated iron-framed building, but it wasn’t until the first half of the 19th century that there were significant moves towards the use of steel as a building material.
The introduction of steel
In 1856, Briton Henry Bessemer developed a method of producing steel that was quicker, less labour intensive, and cheaper. This technique reduced the cost of steel from an average of £70 per ton to approximately £10 per ton. This technique, along with the Open Hearth Furnace developed by Charles William Siemens, meant that, by 1880, wrought iron had been replaced by steel as the primary structural material used at the time. In fact, the Eiffel Tower, which was built in 1889, was one of the very last buildings to be made from wrought iron.
A changing of the guard
In the same year that the Eiffel Tower was completed, construction on the steel Forth Bridge was also completed, signifying a changing of the guard.
Early architectural steel was not as strong as modern steel, and was only slightly stronger than wrought iron, at the time. However, it could be forged, worked, and installed quicker, and it was available at much lower prices. It quickly became the material of choice in the UK and the rest of Europe but did not initially become popular in the US.
The Chicago impact
In the US, the Great Fire of Chicago wreaked havoc on the city’s timber-framed buildings. Properties were destroyed, but the city was rebuilt quickly thanks to the use of iron and, more significantly, steel. New legislation was introduced that initially meant that buildings had to be made from iron columns and beams, non-combustible materials.
However, Chicago continued to grow beyond its original size and, eventually, the only way to expand the city was to build upwards. The Home Insurance Building was completed in 1885 and was 10 storeys high. It utilised a steel frame, offering additional support and structural strength when compared to other building materials – it was the material that made vertical cityscapes a possibility. The Home Insurance Building was only the beginning of a swath of skyscrapers and tall buildings to be constructed using a steel frame.
Another significant name in steel construction is that of Fazlur Khan. Born in 1929, Khan is considered to be the leading light of the Second Chicago School of architecture. He introduced a tubular steel design, which meant a further 30% reduction in the number of raw materials required to build skyscrapers and other buildings.
Today, steel remains one of the most popular building materials. It requires less material when erecting a building. It takes less time and labour to work, and it costs less than other materials. It is also very strong, considered a fire retardant material, which is vital in building construction, and it is readily available. A country’s steel industry is often considered a sign of that country’s economic performance because if more steel is being produced, it suggests that more high-quality buildings are being put up, which means that there must be money flowing through the economy.
Although there has been some depression in the steel industry, no single material has taken over from steel as the material of choice. Metal composites and engineered timber have increased in popularity, but these tend to have very specific uses. One area where steel is actually gaining in popularity, however, is in residential building construction.