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By Steve Jordan
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| This low Queen Anne-style house in Natchez, Mississippi—once the home of the first Black doctor in town—shows how the patterns of metal shingles could turn the roof into the focal point of the building. Metal roofs were also valued for collecting rainwater in places like Key West.
Photo Courtesy of Brian Vanden Brink
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When Carolyn Grieve phoned the Landmark Society of Western New York in 2002, she was looking for help with her old house and her growing list of repairs. Her house in the rural community of Perry is an architect-designed Queen Anne built by her great-grandfather in 1885 and remains in nearly original condition. I visited Carolyn on behalf of the Society and, as we walked around the house discussing peeling paint and leaking roofs, she mentioned that, if it wasn't too expensive, she would like to install a metal shingle roof like the one originally on the house. I told her that I believed metal shingles were both affordable and still available in patterns similar, if not exactly identical, to her originals—that is, if I could locate them. Here's the background I found that can be of use to other old-house owners who want to install a new metal shingle roof or keep the one they have.
Industrialized Shingles
Metal roof shingles were a natural extension of the successful sheet- and corrugated-metal roof industry that flourished from the mid-19th century into the 20th century. Although metal shingles were used prior to the Civil War, the extensive developments after 1875 in building technology, mass production, and efficient railroad shipping created an ideal environment for their popularity. Simply small rectangles stamped from sheet metal and embossed with ornamental designs, early shingles came in a variety of sizes until standardization took hold in the 1880s. The date for the first metal shingle manufactured or sold in the United States has not been established, but trade advertisements indicate they were available in the 1870s. They remained popular up to the 1920s, when they were supplanted by inexpensive, low-maintenance, fire-resistant asbestos-cement and asphalt shingles. The outbreak of World War II signaled the end of the metal shingle's heyday by diverting both metals and manufacturing equipment to the war effort.
Although quality varied and manufacturers' claims were often exaggerated, metal shingles offered many advantages over traditional shingle-type materials. They were lighter and less costly than slate or tile, thereby enabling modest buildings to approach the look of more expensive structures. Unlike wood shingles, metal shingles were rot-proof and fireproof—the latter, a key sales point at a time when roof fires in dense urban areas were common. Metal shingles could often be applied over old roofing materials, making them useful for reroofing as well as new construction. Clever, interlocking edge joints prevented shingles from blowing off in storms or high winds and allowed unskilled workmen to install them effectively without specialized tools. Many manufacturers offered integrated roofing systems that included flashings, ornamental ridge and hip caps, crestings, and finials.
Stamped Style
Most historic metal shingles imitated natural roof materials—wood, slate, and clay tile—but the decorative possibilities of embossing had its own appeal in an age that valued bold or unusual embellishment. Along with familiar motifs like crosses, chevrons, and teardrops, manufacturers might stamp shingles with symbolic patterns, such as the fleur-de-lis or maple leaf, particularly if they offered custom service to architects. Whatever the design, raised ornament added stiffness to the thin metal.
Shingles came in a variety of dimensions—typically 7" x 10", 10" x 14", and 14" x 20". Different sizes allowed the builder, designer, or homeowner to choose a shingle compatible with the scale of the building. Just after 1900, the growing vogue for houses in a host of Mediterranean Revival and eclectic styles, as well as the appearance of new house types like the bungalow, spawned yet another form of metal shingle: the Spanish tile. These "shingles" were designed to simulate the alternating barrel tiles of the old world without the complexity, weight, or expense.
Keeping Your Metal Up
By 1900, metal singles were available in tin (actually, tin-coated steel), zinc, galvanized steel, copper, and bronze. Tin and galvanized iron or steel shingles were usually painted on both sides at the factory for rust and corrosion protection, and when adequately maintained, the shingles lasted many decades.
In fact, it isn't uncommon to see metal shingle roofs that are 100-plus years old and still in good condition. The secret to longevity for a metal roof is regular care. At the first sign of rust, wash the roof clean and paint it with a rust-resistant paint system. Wire brush away loose rust scale, and give any remaining rust a light sanding, but don't use any preparation method that will further deteriorate your shingles. If your roof already has a protective paint coating, your new coating must be compatible with the old one. Most paint stores stock rust-resistant paint systems, or you can special order high-quality zinc chromate primers. Never coat your roof with asphalt cement or any asphalt- or tar-based roof coating. As these coatings fail, they trap water between the coating and shingles, accelerating deterioration.
Though metal shingle manufacturing continues for the modern construction market, most of the distinctive shapes and quirky patterns of a century ago are long gone. Some classic designs, however, are still being made by a few companies, and these can offer a good option for replacing or adding on to a roof covered in historic metal shingles.
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Returning to Metal
When roofer and sheet metal specialist Curt Catalano first looked at Carolyn Grieve's house, he lifted up two layers of asphalt shingles to expose some of the original metal shingles. The original roof had been manufactured by the Cortright Metal Roofing Company of Philadelphia, one of the industry's leaders, and the firm had, in fact, featured the Grieve homestead in their 1908 catalog. Cortright has been out of business for years, but Curt remembered seeing a video tape promotion from Berridge Manufacturing Company that included metal shingles. As luck would have it, Berridge had copied a shingle found on an old church in Texas, and this same pattern was a nearly identical match with the original on Grieve's home. With Curt's help, Carolyn selected the "Classic" shingle in Galvalume (sheet steel coated with aluminum and zinc) and coated in a durable red Kynar 500 finish.
When the shingles, associated flashing, and instructions arrived, Curt's crew began tearing off the multiple layers of old roofing down to the wood deck boards. As is often the case, the original field shingles appeared to have been in good condition when first reroofed, but the original flashing and valleys were deteriorated. As on many houses built in the 19th- and early 20th century, the shingles had been applied over skip sheathing—boards (typically 1"x 6") that were spaced a few inches apart. This spacing promoted air circulation around wood and metal shingles, allowing condensation and other moisture to dry from both sides. Curt's crew kept this sheathing, but they also installed a bituminous membrane (Ice and Water Shield by W.R Grace) along the eaves as secondary protection from leaks and ice dams. Flashing, valleys, and drip edges were all fabricated from 24-gauge steel with the same Galvalume and paint finish as the shingles.
Just like the originals, the new shingles interlock creating waterproof and windproof joints. For extra protection against leaks, Curt formed the valleys with a double-crimp in the shape of a "W" down their middles. In hard rains, this crimp helps prevent water from surging from one roof plane onto the adjacent roof plane and up under shingles. To complete the job, Curt touched up the exposed metal edges of all cut shingles using paint supplied by the manufacturer.
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