Table 3-7.-Weight of Roofing Materials
resistant to fire; however, because of their weight
(table 3-7), they usually require additional structural
framing members and heavier roof decks.
Clay. The clays used in the manufacture of
roofing tile are similar to those used for brick. Unglazed
tile comes in a variety of shades, from a yellow-orange
to a deep red, and in blends of grays and greens. Highly
glazed tiles are often used on prominent buildings and
for landmark purposes.
Clay roofing tiles are produced as either flat or roll
tile. Flat tile may be English (interlocking shingle) or
French. Roll tiles are produced in Greek or Roman
pan-and-cover, Spanish or Mission style (fig. 3-27).
Roll Tile. Roll tile is usually installed over two
layers of hot-mopped 15-pound felt. Double-coverage
felts, laid shingle fashion, lapped 19 inches, and mopped
with hot asphalt, may be required as an underpayment.
The individual tiles are nailed to the sheathing through
prepunched holes. Special shapes are available for
starter courses, rakes, hips, and ridges. Some
manufacturers produce tiles in special tile-and-a-half
units for exposed locations, such as gables and hips.
Figure 3-27.-Types of clay roof tiles.
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