Clay Concrete Tile

Clay tile is produced by baking molded clay into tile. The density of the clay is determined by the length of time and temperature at which it is heated. Tiles may be glazed and also may have surface texture treatments applied. As a result, there are a wide variety of tile profiles, styles, finishes and colors available. In addition, there may be separate accessory tiles—matched to each field tile design—of various shapes designed for use on ridges, hips, hip intersections and gable ends. Installation methods depend on the nature of the tile being installed; that is, whether it is two piece, one piece, interlocking or flat.

Concrete tiles are made of portland cement, sand and water in varying proportions. The material is mixed and extruded on molds under high pressure. The exposed surface of a tile may be finished with cementitious material colored with synthetic oxide additives. The tiles are cured to reach the required strength. They generally have lugs on their undersides for anchoring to batten strips. There are additional waterlocks or interlocking ribs on the longitudinal edges that impede movement and prevent water infiltration.

As with clay tile, there are a wide variety of profiles, styles, finishes and colors available. Color may be added to the surface of a tile or dispersed throughout (color through). Special texture may be added in surface treatment. Each type of tile roof system may make use of separate ridge, hip, hip intersection, gable end and finial accessory tiles of various shapes in addition to field tiles.

Many different types and combinations of securement methods are used for the various types of roof tile. To select a method of securement, many conditions need to be considered: wind, deck type, seismic considerations, slope, building codes, local practices and manufacturer recommendations. Fasteners should be made of noncorrosive materials that will remain serviceable in the intended environment for the roof’s design life.

  • • Nails—Nailing is the most common method. NRCA recommends that roofing nails be 11- gauge or 12-gauge galvanized steel or the equivalent corrosion-resistant roofing nails. Nail heads should be low-profile, smooth and flat. Shanks should be barbed or otherwise deformed for added pull-out strength. Nails should be long enough to penetrate through all layers of roofing materials and extend through the underside of the roof deck or penetrate at least 3/4 inch into wood plank or board decks.
  • • Wire tie and strapping systems—Hanging tile with wire is used on non-nailable decks, insulated decks or where fastening through metal flashings needs to be avoided.
  • • Clips—Nose or butt clips sometimes are used in conjunction with other attachment methods in high-wind or seismic areas.
  • Lug-hung-tile—Many types of tile have formed undersides near their heads that may be hung over a batten. Lug hanging tile usually is used in combination with other securement methods.
  • • Bedding Tile—Laying tile in a bed of mortar of foam adhesive is common in some areas of North America where freeze/thaw conditions are not encountered. Bedding often is used in combination with other securement methods.