Sponsored by PRIVATE RESIDENCE, FLORIDA. Taking Stock of TERRA COTTA ROOF TILES

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1 Sponsored by PRIVATE RESIDENCE, FLORIDA Taking Stock of TERRA COTTA ROOF TILES

2 Few roofing materials come close to the superlatives earned by terra cotta tile decadeslong life, beautifully traditional, fireproof, highly cost-effective over time, inherently sustainable and green but if you re planning for a new roof, or to expand an existing roof, here s some other terms and details to consider when specifying tile. SEVEN CANYONS, ARIZONA CLIMATE The U.S. is a tremendous country with multiple climate zones, so it s important to choose a roof that will withstand the weather conditions where it is installed. In many areas temperatures can regularly rise above 100 degrees F. or dip below zero degrees F. even rapidly swinging between both extremes in some locales. Under such conditions, building materials that absorb moisture can be vulnerable to the phenomenon of freeze-thaw that, in terra cotta, can cause tiles to spall and crack. For reliable service in all zones, terra cotta roof tile should meet or exceed ASTM Standard C1167, Grade 1, to ensure it provides resistance to severe frost action and water absorption.

3 PRIVATE RESIDENCE, GEORGIA ROOF PITCH To shed water most effectively, and to help underlayments be the backup protection against winddriven rain, terra cotta tiles should be installed on steep-slope roofs and at the best pitch for the profile. Generally, this means a pitch of not less than 4-in-12 (18-degree angle), though some interlocking types may be installed as low as 3-in-12. Steep-slope roofs also highlight the beauty of tiles to their best advantage, and aid in carrying the load of the terra cotta, which is a dense, hefty material. Traditional profile roof tiles can vary in weight from 600 lbs. to 1,200 lb. per square (100 sq. ft.) and therefore may require heavier roof framing and bracing than conventional construction for proper structural support.

4 PRIVATE RESIDENCE, ALABAMA PROFILES & INSTALLATION While there s no simple way to describe the inventive mix of profiles and attachment methods that compose traditional terra cotta tile roofs, it helps to think of them as being either interlocking or overlapping. As the name suggests, interlocking tiles secure to one another, usually via some system of mating lip and hook. They are also typically nailed to the roof deck or wood nailers. Overlapping tiles come in many shapes some ancient and generally fall into two groups: flat tiles and pantiles. Flat tiles are, indeed, flat and slablike, similar to roofing slates, and typically install with nails similar to slates. Lugs on the back the tile may help it hang on a horizontal nailer, and tiles may interlock at tops and sides. Pantiles, in contrast, are those profiles that are rounded in some manner, a group that includes versions of iconic Spanish tiles ( S - shaped), Barrel or Mission tiles (half-round cylinders, sometimes tapered) and Roman tiles (flat with a rounded side or two). Pantiles use several installation methods, according to their design and maker. Spanish and Roman tiles are typically attached with nails or screws that are covered by the succeeding course. Barrel and Mission tiles use a cover-and-pan system where the joint between each pair of adjacent, upturned, half-cylinder tiles (attached to the roof deck) is capped by an inverted, half-cylinder tile to make a water-shedding course with a pan-cappan-cap-pan layout. Cap tiles are traditionally held in place either by securing with copper wires or nailing to vertical wood battens. In addition to the ridge tiles, hip tiles, and other accessory pieces necessary to complete an installation, terra cotta tile is also traditionally made in specialized profiles for covering the eye-catching and fanciful geometrical roofs shapes so characteristic of historic architecture, such as cones, domes, and the converse and convex surfaces of Mansard and ogee roofs. Terra cotta tile protects and beautifies all kinds of buildings in all areas and times. Despite the evident associations with certain cultures or eras think French or Spanish tile in America the choice of a roof tile profile has frequently been less about taking cues from history than the building type, economics, and often simply being in-step with the local roof-dujour. Ever a substantial, but highly durable and prominent investment, tile roofs have always found favor with long-term building owners, such as banks, libraries, train stations, churches, colleges, and city halls not to mention savvy homebuilders. Tile roof popularity no doubt benefitted from improved manufacturing methods in the 1870s, and it enjoyed a tremendous boost from World s Fairs in 1876 and 1890 where it topped many showpiece structures. In houses, tile became integral with the Richardson Romanesque style of the 1890s, and the darling roof for bungalows and other Arts & Crafts dwellings of the early 20th century, but beyond this it has tended to transcend most architectural styles. According to A. Tab Colbert of Ludowici Roof Tile, Spanish and Mission tiles are inclined to dominate in Texas, but go to Florida and there are plenty of interlocking flat tiles as well. Chicago, he says, likes French. Greek churches and even many Catholic churches also appear in French tiles along with barrel tiles. In Brooklyn you ll see an awful lot of Spanish and Mission, he says. There are little enclaves all over; it really depends.

5 IMPRESSIONIST COLOR EXAMPLES ON LUDOSLATE TILE PRIVATE RESIDENCE, NORTH CAROLINA COLORS AND TEXTURES Color adds a whole other dimension to terra cotta roof tiles in fact, the opportunity to work in multiple dimensions. Tile color begins with the terra cotta itself, a material that, depending upon the clay source, can range from a deep reddish brown (where iron oxide is rich) to light buff and beige. Glaze applied to the clay body, then fired in a kiln, opens up many more color possibilities. Generations ago, most tile colors were a variety of reds, oranges, and greens, now considered traditional and still available today. Since the mid-20th century the palette for many tiles has expanded dramatically to dozens of standard colors, with modern technology making possible almost countless blends. Other visual enhancements include tooling textures into the clay surface, such as brushed and weathered effects that emulate aged tiles, and sheens that are produced in the glaze. A high-gloss sheen, for example, adds to the visual statement, while a matte sheen may be preferable where intense sunlight would detract from the color of a glossy roof.

6 PRIVATE RESIDENCE CLAY AS AN ALTERNATIVE Given terra cotta s long history as a highly mailable material, now with a versatile command of color, it s only a short step to replicating the look of other roofing types particularly natural slate and wood shingles. In fact, the wood shingle roofs covering some of America s most famous historic buildings are, in reality, terra cotta tile. The tradition continues today in modern terra cotta tiles that are far more durable than wood shingles, weigh less than natural slate even less than most traditional profile tiles and can, in many cases, be custom-color blended to evoke the shifting tints and shadow lines of a quarried or spilt material. Moreover, terra cotta can go the originals one better in weatherresistance when the tiles are interlocking.

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