Architectural metals
[1] Water pipes were frequently constructed of lead, until its health hazards were publicised in the late 19th century.
Lead roofs in regions with large temperature fluctuations, such as the mid-Atlantic states, experienced deterioration from constant expansion and contraction, called fatigue.
However, persons who worked with sheet metal were called tinsmiths, so the term could have sprung from this title.
[3] Tinplate was a type of architectural material consisting of sheet iron or steel coated with tin.
The methods employed a “hot dipping” process to coat sheet iron with zinc.
Decorative architectural elements were frequently cast in zinc, since it molded readily, was inexpensive compared to stone, and could be painted to imitate more expensive metals.
Stamped swags, rosettes, fleur-de-lis and acanthus leaves provided popular decorative ornamentation of both exteriors and interiors by the late 19th century.
[7] Exact alloy composition is subject to manufacturer and is a color determinant in zinc's final patina.
Over time, zinc develops its distinctive patina, transforming from a shiny silver to a matte bluish-grey.
Today, galvanized steel and pure zinc material, usually Double Locked Standing Seam panels, are used for roofing a variety of buildings.
At the end of its service life, zinc building products can be recycled indefinitely without loss to chemical or physical properties.
The use of architectural grade zinc can help building qualify for LEED certification due to its high recycled content and sustainability.
Roofing copper can be folded readily into waterproof seams, or shaped over curved frameworks for cupolas and domes.
[9] Copper was also used for decorative purposes, including architectural ornaments, siding, ceilings or sculptures.
Different percentages result in a range of colors, including silvery-white, yellow, slight blue, green or pink.
Its advantages as a roofing material included its ability to be brazed, welded, or soldered in place to provide a watertight, continuous cover.
Until the mid-19th century, the use of wrought iron in buildings was generally limited to small items such as tie rods, straps, nails, and hardware, or to decorative ironwork in balconies, railings fences and gates.
Around 1850 its structural use became more widespread as iron mills began to roll rails, bulb-tees, and eventually I-beams.
Decorative uses have included stairs, elevators, lintels, grilles, verandas, balconies, railings, fences, streetlights, and tombs.
Today, cast iron is used for plumbing fixtures and piping in new construction, and its structural and decorative use is used occasionally through historic preservation practices.
Decorative steels used in buildings include: Much like copper, Aluminium is highly resistant to corrosion.
[13] Aluminium was unavailable at reasonable cost or in sufficient quantities for general architectural use until after the beginning of the 20th century.
