Cast-iron architecture

Architectural use

In Europe, cast iron had been occasionally used with architectural embellishment in the Middle Ages, such as fire backs with cast figures and scenes. The improvements in techniques in the late 18th century led to the possibilities of finer castings, allowing decorative objects such as statuary and jewelry to be mass-produced. Following the development of the material as for structural purposes, it was soon adapted for uses that were both decorative and structural in all manner of buildings, structures and objects.

Early balustrades, railings and memorials

As soon as improvements in techniques led to finer castings, designers exploited the decorative possibilities. As early as 1775, noted architect Robert Adam joined with the Scottish Carron Company iron works to produce balcony railings in imitation of wrought iron, such as the railing for the Adelphi in London (a pattern that was still produced into the 1830s). Another very early large scale example is the delicate fence of the Summer Garden in Saint Petersburg, designed by Georg Von Veldten, built between 1771 and 1784, which also imitated wrought iron, and is considered the pinnacle of cast iron design in the city. Other well known architects were early adopters of the material; John Nash employed cast iron as part of the structure of his landmark 1820s Royal Pavilion in Brighton, and German architect Karl Friedrich Schinkel was an enthusiastic early adopter, using cast iron for memorials such as the 20m tall Gothic Revival Kreuzberg War Memorial in 1821, and the delightful nautical seahorses and mermaids in the balustrade of the 1820s Castle Bridge in Berlin.

In Saint Petersburg, cast iron was used on the many bridges, sometimes as the supporting structure, but especially for the decorative railings and sculptural embellishments, including the chain-suspension 1826 Bank Bridge, with its distinctive cast iron griffin sculptures and elaborate balustrades, the 1840 Pevchesky Bridge, the 1842 Anichkov Bridge (a copy of the Berlin Castle Bridge), and more seahorses on the 1843–1850 Annunciation Bridge.

Prefabricated and transportable buildings

Since it could be used for all the structural members that would be cast in a foundry and then transported to site for erection, it was soon realised it could just as easily be transported anywhere in the world. The Commissioner's House of the Royal Naval Dockyard, Bermuda designed by Edward Holl and built in the 1820s, is considered to be the first residence that used cast iron structure, for the verandahs, and floor and roof framing, and proved the concept of prefabrication and transportation long distances. Designers and foundries in the UK, France and Germany went on to produce all kinds of prefabricated cast iron structures and items for shipping to the colonies, from decorative elements to structural components to entire buildings. During the Victorian gold rush in Australia in the 1850s hundreds of various types of prefabricated structures were shipped out from foundries in England and Scotland, in timber, cast or wrought iron, or a combination, often with corrugated iron for the walls and roof. They included houses, stores, at least three complete churches, and an entire theatre; the most elaborate surviving structure in Australia is the completely cast iron Corio Villa, in Geelong. There are at least 100 surviving or part surviving prefabricated buildings, which in 2021 were to be nominated for World Heritage significance.

Markets were a type of structure that lent themselves to prefabrication and shipping, such as the structure of the Mercado Centrale in Santiago, Chile, which was shipped out from Glasgow firm Laidlaw & Sons in 1869. The Marché en Fer (Iron Market) in Port-au-Prince, Haiti, fabricated in Paris, was reputedly intended as a railway station for Cairo in 1891 but was purchased by the Haitian government instead.

An early type of completely prefabricated building was the large storage shed at dockyards. The Boat Shed (Number 78) at Sheerness Naval Dockyards, built 1856–60, is constructed entirely of a cast and wrought iron members, braced as portal frames, with extensive window and timber infill panels forming the external walls. Though not entirely of cast iron, it is the earliest large metal framed building still standing, and a pioneer in the development metal frames.

Watson's Hotel in Mumbai was prefabricated in England and built in 1867–69, using brick infill panels in a heavy and decorative cast-iron frame and is one of the largest completely cast iron framed building (as opposed to market or shed) in the world. Possibly the largest prefabricated cast iron structure is the Bulgarian St. Stephen Church in Istanbul, shipped out from Vienna in the late 1890s.

French use, integrated with decorative scheme

The Menier Chocolate Mill in Noisiel, completed in 1872, is often cited as the first building with an expressed metal frame. It was not however the first given earlier examples, but it is one of the most attractive (and some of the framing is hidden by the bricks). Designed by Jules Saulnier, it was an expression of a French approach that included an exposed metal frame as part of an overall decorative scheme, often using polychrome brick and tiles, with other examples later in date.

Verandahs and porches

The use of decorative cast iron as railings, fences and balconettes gradually gained popularity in Regency Britain and post-Napoleonic France as a cheaper alternative to the wrought-iron railings that only the wealthy could afford. The idea was exported to the colonies of both countries with hot climates as porches or verandahs, where it formed both decoration and structure.

New Orleans' French Quarter has the most famous and elaborate examples and the greatest concentration, with light, lacy often multi-level porches (known in New Orleans as galleries) on over 400 buildings, transforming the area from the 1850s to 1880s. A few similar porches can be found in Savannah's Historic District, and the Church Hill and Jackson Ward neighborhoods in Richmond, though there it is mostly used for stair, porch and balcony railings. Numerous foundries in all three cities produced unique ornamental and structural designs in cast iron.

In Australia, similar porches of usually only one or two levels, known as verandas, decorated with 'cast-iron lace', became a standard feature, shading the fronts of nearly every house, terrace house, pub and shop from the 1850s into the 1900s. Foundries in most cities and (with 42 in Melbourne alone) and many country towns began by reproducing imported designs in the 1850s and then developing their own, sometimes featuring Australian fauna such as cockatoos and koalas, but most featured flowing classically derived or vine-like patterns. After a period in the 1950s–60s when cast iron verandahs were routinely demolished, since the late 1970s they made a revival, and numerous foundries still provide historic patterns to order. Decorative cast iron used in a similar way can be found in other former British colonies including South Africa, Malaysia and India.

Cast-iron facades

In the 1840s the cheapness and malleability of cast iron led James Bogardus of New York City to develop the idea of buildings using cast iron for complete decorative facades, which were far cheaper than traditional carved-stone, but could be painted to give the appearance of stone. His first was put up in 1848, quickly followed by many more, and he promoted the idea in a pamphlet Cast Iron Buildings: Their Construction and Advantages (1858). The idea was taken up by other notable pioneer Daniel D. Badger, whose iron works in the East Village turned out "some of the most dramatic iron buildings this country has ever seen", most notably the E. V. Haughwout Building in 1857. Particularly popular for warehouse / industrial buildings, but also for department stores, the streets of the SoHo and Tribeca areas of New York and what is now known as the Old City area of Philadelphia were soon lined with elaborate Renaissance Revival style facades. Warehouse districts in smaller US cities soon also saw many examples, but most have been demolished. The West Main District, Louisville Kentucky has the most surviving examples, with about 10 in a three block stretch. The Skidmore/Old Town Historic District in Portland, Oregon also features a number of examples remaining from a once extensive district. In Europe, cast-iron architecture was never popular, except in the growing industrial city of Glasgow, Scotland, where a few survive, such as the 1872 Ca d’Oro Building.

Greenhouses, exhibitions and markets

Cast iron also became the standard support structure in the construction of larger greenhouses. English architect and gardener Joseph Paxton experimented with frameworks of timber, cast-iron and glass in the 1820s and 30s, designing ever larger structures, often prefabricated, culminating in the monumental Crystal Palace exhibition hall built in London in 1851. The success of the concept spawned many imitators, as both exhibition halls and greenhouses, which were almost universally constructed of cast iron (sometimes in combination with wrought-iron) in the 19th century. The Palm House at the Belfast Botanic Gardens, completed in 1840, is an early surviving example.

Cast iron was particularly useful to provide the entire structure of market halls, with a solid roof and open sides or highlight windows, and by the end of the 19th century nearly every new market in Europe (and most in Latin America) were cast-iron, some vast and elaborate, such as the 1850s Les Halles in Paris (demolished).

An interesting application is for a winter garden, with a solid roof but extensive glass walls, such as the Spa Colonnade in the spa town of Mariánské Lázně in the Czech Republic, built in 1889, which features an elaborate roof structure and extensive Neo-Baroque decorations in the facade, all in cast iron.

Arcades

Cast iron was quickly adapted to allow ever wider glass roofs on the then new idea of glass-roofed shopping arcades in Paris in the first decades of the 19th century. The idea spread across Europe and the United States in ever grander structures, and the largest examples had vast arched roofs in cast iron, such as the Galleria Vittorio Emmanuel in Milan.

Roofs, domes and atriums

Cast iron was used for the construction of large domes, as early as 1811 with the huge dome of the Bourse de commerce in Paris, originally the Corn Market and clad in copper (later replaced with glass). The central four storey circular hall and towering glass dome of the long-demolished 1849 London Coal Exchange was an early and spectacular use of the material as both structure and architecture.

The most famous example is the United States Capitol dome, built 1855–66 and made entirely of cast iron. The dome was designed by the architect Thomas Ustick Walter, and fabricated by the New York iron foundry, Janes, Fowler, Kirtland & Co. The dome consists of nearly 9 million pounds of cast iron. Another important example is the dome of Saint Isaac's Cathedral in St Petesburg, Russia, built in the 1830s.

The 1872 George Peabody Library in Baltimore is a similarly elaborate atrium with glass roof, where all the structural members are also decorative and made of cast iron. The lofty glass roof of Milan's Galleria, built 1865–77, is both a dome and glass roofed shopping arcade, the grandest ever built. Later glass roofs such as that of the Grand Palais in Paris employed wrought iron or steel.

Cast iron lent itself to creating thinner supports in churches. An early example dates from 1837, when architect Louis Auguste Boileau supported the interior of the Eglise St-Eugene Ste-Cecile in Paris on slim cast iron columns and ribbed vaulting imitating the Gothic style, but thinner than stone would have allowed.

Two famous examples of cast iron as both support and decoration of a roof on slender columns are the two great mid 19th century libraries of Paris, the double-arched roof of the Bibliothèque Sainte-Geneviève reading room, built 1843–51, by architect Henri Labrouste, who also designed an even more elegant multiple-domed reading room for the Bibliothèque nationale de France, built in 1861–68.

Street furniture and park items

Cast iron, a durable material that could take on any shape, was also popular from the mid 19th century for street furniture. Not only park and building fences, often with elaborate gates, but also fountains, street lamps, bollards, tree grates and guards, as well as the UK red post box, and in Paris it was used for the elaborate advertising columns, newspaper kiosks and pissoirs the city is known for (though almost all are now contemporary reproductions in other materials). In the 1870s philanthropist Charles Wallace funded the installation of numerous ornate drinking fountains across Paris, and over 100 Wallace Fountains are still in use. Decorative street lamps in cast iron were used all over the world, from gas lamps in the second half of the 19th century to electric ones in the first decades of the 20th – a collection of examples used in California in the 1920s and 30s now form a display outside the Los Angeles County Museum of Art, called Urban Light. When underground trains were established in the 1890s–1900s, the stairs located in pavements were often housed in elaborate cast iron structures, notably the long demolished New York City Subway entrances (one survives at City Hall station outside New York City Hall), and the famous Art Nouveau Paris Métro entrances by Hector Guimard.

For the same reasons, cast iron was also popular for structures within parks and gardens, both public and private, as well as on public promenades, used for fencing, seating, lamp posts, large fountains and drinking fountains, statues, decorative bridges, covered walkways, gazebos and bandstands. The 1885 Morisco Kiosk in Mexico City is a particularly elaborate example of the latter (though this may be wrought rather than cast iron). The 1870s Victoria Embankment in London features particularly ornate examples, with entwined dolphins supporting elaborate lampposts, and benches with sphinxes or camels as end panels.