Roofing system and roofing tile

Roofing system and roofing tile

Pictures for this patent

Abstract

The present invention provides an improved roofing tile and roofing tile system that simulates the appearance of wood shake and has an improved strength to weight ratio. One embodiment of the roofing tile system includes two unique tile profiles, an "A" profile and a "B" profile, wherein tiles having an "A" profile are alternately or randomly installed adjacent tiles having a "B" profile to simulate the appearance of wood shakes. In addition, each roofing tile is formed of a clay material and includes ribs that extend normally from a lower face of the tile, which improves the strength to weight ratio of each tile. Furthermore, each tile includes touch points that extend from the a face of the tile to engage receiving portions on a tile positioned vertically adjacent to the tile, which prevents the tiles from moving relative to each other.

Roofing system and roofing tile

Claims

1. A roofing tile made of clay material that simulates the appearance of a wood shake, said roofing tile comprising, said roofing tile further comprising: a head end; a nose end; a body intermediate said head end and said nose end; a wood grain design on an upper face of said roofing tile adjacent to said body and said nose end; and a plurality of primary ribs extending substantially normally from a lower face of said roofing tile and extending along a length of said body from said head end to said nose end; a plurality of secondary ribs extending substantially normally from a lower face of said roofing tile and extending along a length of said body, said secondary ribs having a length that is shorter than a length of said primary ribs; wherein each of said ribs comprises at least one wide portion and at least one narrow portion, and said wide portion being positioned adjacent one or more portions of said tile having less flexural strength.

2. The roofing tile of claim 1 wherein said body includes: a left side portion, a right side portion, and a center portion disposed intermediate said side portions, wherein said center portion has a reduced cross-section from said side portions and wherein a first of said one or more ribs is positioned under a transition area between said left side portion and said center portion, a second of said ribs is positioned under a transition area between said right side portion and said center portion, and a third of said ribs is positioned under a transition area between said head end and said center portion.

3. A roofing tile system for simulating the appearance of a wood shake roof, said system comprising: a first roofing tile having a first unique profile, said first roofing tile comprising: a head end, a nose end, and a body, wherein said nose end and said body have a substantially uniform cross-section and include a simulated wood grain design on an upper face of said first roofing tile; and a second roofing tile having a second unique profile, said second unique profile being different than said first unique profile, said second roofing tile comprising: a nose end, a head end, and a body, said body including a center portion intermediate a left side portion and a right side portion, wherein said center portion has a reduced cross section than said side portions, and said side portions have substantially the same cross section as said body of said first roofing tile; wherein said first tile is installed horizontally adjacent to said second tile.

4. The roofing tile system of claim 3 further comprising a plurality of said first roofing tiles and a plurality of said second roofing tiles, wherein said first roofing tiles are assembled horizontally adjacent to and in an alternating arrangement with said roofing second tiles.

5. The roofing tile system of claim 3 further comprising a plurality of said first roofing tiles and a plurality of said second roofing tiles, wherein said first roofing tiles are randomly assembled horizontally adjacent to said first roofing tiles and said second roofing tiles.

6. The roofing tile of claim 3 wherein said center portion of said second roofing tile has a shorter length than said side portions of said second roofing tile, and said side portions of said second roofing tile have substantially the same length as the body of said first roofing tile.

7. A roofing system comprising a plurality of roofing tiles, each of said tiles comprising: a head end having an upper transverse ridge and a lower transverse ridge; a nose end; a first face comprising at least one first touch point adjacent said head end and at least one second touch point adjacent said nose end, said first and second touch points extending substantially normally from said first face; and a second face, said second face being opposite said first face and said second face defining a first touch surfaces adjacent said upper transverse ridge and a second touch surface adjacent said lower transverse ridge; wherein, said first touch point of a first tile is adapted for engaging said first touch surfaces of a second tile that is stacked vertically adjacent said first tile to prevent relative movement of said first tile and said second tile, and said second touch point of said first tile is adapted for engaging said second touch surface of said second tile positioned in a below laid-course to align the overlap of said nose end of said first tile with said head end of said second tile.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from provisional U.S. Application No. 60/573,708 entitled "Method and Apparatus for Manufacturing and Installing Improved Roofing Tiles," which was filed on May 20, 2004 and which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

[0002] This invention relates in general to roofing, and particularly relates to the use of lightweight yet structurally sound clay material roofing tiles that simulate wood shake roofing.

BACKGROUND OF THE INVENTION

[0003] In the field of roofing, it is well known to use wood shakes as roofing elements. Typically, the wood shakes are installed in an overlapping manner to divert water. However, wood shakes have disadvantages, including their flammability and their tendency to leak after sufficient weathering. Nevertheless, consumers have shown a preference towards wood shakes due to their desirable appearance.

[0004] Roofing elements that simulate wood shakes and are comprised of nonflammable materials, such as concrete, metal, or clay (sometimes called "terracotta"), have become known. However, roofing elements made to date with these alternative materials present additional disadvantages. For example, roofing tiles made of concrete or clay tend to be heavy, weighing between 8 and 11 pounds per square foot, making them unsuitable for remodeling or re-roofing roofs that previously used lighter roofing elements, such as wood shakes or asphalt roofing tiles. In addition, previous attempts to reduce the weight of the concrete or clay tiles significantly have resulted in a reduction in the flexural strength of the tiles. Furthermore, known concrete and clay roofing tiles are categorized as a lower grade of building material because of their inability to provide adequate protection for severe climate weathering. For example, known tiles are typically characterized as having a Grade 1 Weathering Index of less than 500 (see ASTM C1167-96, Table 1).

[0005] As another example, metal pressed roofing tiles tend to be limited to shapes with identical contours on both the top and bottom surfaces. Further, tiles made with alternate materials, such as concrete and metal, have a tendency to rub against one another during shipping, causing unwanted scratching and chipping on the surfaces of the tiles.

[0006] Therefore, there is a need in the art to provide roofing elements that simulate wood shakes and have improved weathering capabilities and an improved strength to weight ratio.

SUMMARY OF THE INVENTION

[0007] The present invention overcomes deficiencies of the prior art by providing an improved roofing system and roofing tile that simulate the appearance of a wood shake roof and have improved weathering capabilities, an improved strength to weight ratio, and improved packing, or shipping, characteristics. One embodiment of the roofing tile system includes tiles having one or two unique profiles, an "A" profile and a "B" profile, that are alternately or randomly installed adjacent each other to simulate the appearance of wood shakes. Each tile having an "A" profile has a uniform cross-section throughout the body of the tile, and each tile having a "B" profile has a depressed center portion and two raised side portions throughout at least a portion of the body of the tile, wherein the two raised side portions have substantially the same cross-section as the tiles having an "A" profile.

[0008] In addition, each tile includes a plurality of ribs that extend from a lower face of the tile. By positioning the plurality of ribs on the lower face of the tile below portions of the tile that have reduced flexural strength, the weight of each tile is reduced while the strength of each tile is maintained. The width of each rib may also be varied along the length of the rib to provide additional strength to portions of the tile that have reduced flexural strength.

[0009] Furthermore, each tile includes upper touch points that prevent the tiles from moving relative to each other when vertically stacked together and lower touch points that provide a headlap alignment guide for the next-laid course in a roofing installation. The upper and lower touch points extend from the lower face of the tile and seat adjacent to upper and lower touch surfaces, respectively, on a tile positioned vertically adjacent to the tile.

[0010] Other features and advantages of the present invention will become apparent upon reading the following detailed description of exemplary embodiments of the invention when taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1 is a perspective view of unique tile configurations 20A according to one embodiment of the invention;

[0012] FIG. 2 is a top view of the upper face of tile configuration 20A of FIG. 1;

[0013] FIG. 3 is a perspective view of a lower face of tile configuration 20A of FIG. 1;

[0014] FIG. 4 is a top view of the lower face of tile configuration 20A of FIG. 1;

[0015] FIG. 5 is an front view of tile configuration 20A of FIG. 1;

[0016] FIG. 6 is a end view of tile configuration 20A of FIG. 1;

[0017] FIG. 7 is a side view of the left side of tile configuration 20A of FIG. 1;

[0018] FIG. 8 is a side view of the right side of tile configuration 20A of FIG. 1;

[0019] FIG. 9 is a perspective view of unique tile configuration 20B according to one embodiment of the invention;

[0020] FIG. 10 is a top view of the upper face of tile configuration 20B of FIG. 9;

[0021] FIG. 11 is a perspective view of a lower face of tile configuration 20B of FIG. 9;

[0022] FIG. 12 is a top view of the lower face of tile configuration 20B of FIG. 9;

[0023] FIG. 13 is an front view of tile configuration 20B of FIG. 9;

[0024] FIG. 14 is a end view of tile configuration 20B of FIG. 9;

[0025] FIG. 15 is a side view of the left side of tile configuration 20B of FIG. 9;

[0026] FIG. 16 is a side view of the right side of tile configuration 20B of FIG. 9;

[0027] FIG. 17 is a perspective view of an exemplary rotating mold 10 that includes multiple tile-shaped cavities 11A, 11B for receiving clay;

[0028] FIG. 18 is an end view of the mold 10 of FIG. 17, viewed along its axis of rotation and illustrating its interaction with a reciprocating top mold member 14;

[0029] FIG. 19 is a side view illustrating an exemplary installation of tiles atop a support surface 43;

[0030] FIG. 20 is a plan view illustrating an exemplary installation of tiles atop a support surface; and

[0031] FIG. 21 is a perspective view of an exemplary installation of tiles atop a support surface.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0032] The present invention addresses the above needs and achieves other advantages by providing a roofing system that includes roofing tiles that have one of at least two profiles. In one embodiment, a portion of the tiles has an "A" profile, and a portion of the tiles has a "B" profile. When the tiles having an "A" profile are installed alternately or in a random fashion with tiles having a "B" profile, the tiles simulate the appearance of a wood shake roof, as shown in FIG. 21. The structures of each of the profiles according to one embodiment are described below in the section "Tile Structure," and exemplary methods of manufacturing the tiles and installing the tiles are described below in the sections "Method of Manufacturing the Tiles" and "Method of Installing the Tiles," respectively.

[0033] Tile Structure

[0034] FIGS. 1 through 8 illustrate an embodiment of a singe roofing tile having an "A" profile. The "A" profile tile 20A includes an upper face, a lower face, a "head" end 32A, a "nose" end 33A, and a body 36A extending between the head end 32A and nose end 33A. As shown in FIGS. 1, 2 and 6, the upper face of the tile 20A is substantially flat, with the exception of the simulated wood grain design on the body 36A and the nose end 33A. The simulated wood grain design gives each tile 20A the appearance of a conventional wood shake member with natural variances. Further, as shown in FIG. 5, the gaps and shadows that are expected in a wood shake roof are maintained at the nose end 33A of the tile 20A, such that two overlapping tiles have irregular clearance.

[0035] The body 36A includes a left portion 23A, a right portion 24A, and a center portion 22A that extends between the left portion 23A and the right portion 24A, as illustrated in FIG. 1. The center portion 22A has substantially the same elevation as the left and right portions 23A, 24A, resulting in a substantially uniform cross section through the body 36A and extending towards the nose end 33A. Further, the upper face of the nose end 33A is level and has a slightly higher elevation than the head end 32A of the tile 20A, which is shown in FIGS. 7 and 8.

[0036] As shown in FIGS. 2 and 6, the head end 32A includes two transverse ridges 250A, 251A that extend across the upper face of the tile 20A. The ridges 250A, 251A lie along a substantially common transverse axis C. The lower ridge 251A is substantially straight so as to provide a "straight edge" and stable support for tiles that are placed atop the lower ridge 251A in the next-laid course. The portion of the tile 20A between the lower ridge 251A and the body 36A defines a lower touch surface 312A for receiving a lower touch point 307A, 307B located on the rear side of an above-stacked tile, which is discussed in more detail below in relation to FIGS. 3 and 11. The upper ridge 250A jogs back and forth, defining upper touch surfaces 310A for receiving upper touch points 311A, 311B located on the rear side of an above-stacked tile, which is discussed in more detail below in relation to FIGS. 3 and 11. In addition, the upper ridge 250A provides a water barrier for preventing water from backing up behind the tile 20A or from reaching behind the tile 20A in the case of wind driven rain.

[0037] The upper 250A and lower ridge 251A further define an intermediate channel 255A that provides a water channel for wind driven rain. The intermediate channel 255A diverts the rain to the edges of the left side of the tile 20A and into channel 26A of engagement member 25A or to the right side of the tile 20A and off of downwardly directed ledge 30A of engagement member 29A. Channels 26A, ledge 30A, and engagement members 25A, 29A are discussed below in relation to FIGS. 1, 4, 7, and 8.

[0038] In addition, apertures 260A, 261A for receiving fasteners are provided in the upper 250A and lower ridges 251A, respectively. Fasteners are engaged through the apertures 260A, 261A to secure the tile 20A to the roof. As shown in FIG. 2, aperture 260A is located in a portion of the upper ridge 250A and aperture 261A is located in a portion of the lower ridge 251A. The additional cross sectional area of each ridge 250A, 251A provides more strength for the tile 20A, reducing its tendency to split. Additionally, the ridges 250A, 251A provide a raised surface against which a nail or other suitable fastener can be driven.

[0039] As shown in FIGS. 3 and 4, the lower face of the tile 20A includes a plurality of strategically placed structural ribs 300A to provide lightweight yet structurally sound support for the tile 20A. The ribs 300A, which extend normally from the lower face of the body 36A, include two edge ribs 301A, one center rib 303A, and three secondary ribs 305A that extend along the length of the tile 20A. The two edge ribs 301A extend the length of the tile 20A from the head end 32A to the nose end 33A to provide support for the edges of the tile 20A, and the center rib 303A extends the length of the tile 20A from the head end 32A to the nose end 33A to provide support for the center portion 22A. The three secondary ribs 305A, which are shorter than the edge ribs 301A and the center rib 303A, extend lengthwise and adjacent the body 36A of tile 20A. Further, the three secondary ribs 305A are interspaced between the edge ribs 301A and the center rib 303A to provide intermediate support to the portions of the tile 20A between the left 23A and right portions 24A and the center portion 22A. Thus, by having a reduced length and being positioned between the edge ribs 301A and the center rib 303A, the secondary ribs 305A provide additional strength for the tile 20A between the edge 301A and the center portions 301A without adding unnecessary weight.

[0040] The ribs 301A, 303A, 305A are substantially evenly spaced, providing superior strength when the tile 20A is subjected to flexural strength testing or actual field conditions, such as exposing the tiles to foot traffic. In addition, the secondary ribs 305A and the center structural rib 303A vary in width such that the width of each rib 305A, 303A increases adjacent portions of the tile 20A that have a reduced flexural strength. For example, as shown in FIGS. 3 and 4, the width of each rib 303A, 305A increases as the rib approaches the center of the body 36A and decreases as the rib 305A, 305A approaches the head end 32A and the nose end 33A. As a further example, the width of each rib 303A, 305A may be increased if the rib 303A, 305A is adjacent an area of the tile that has a reduced cross-section. Varying the thickness of the ribs 303A, 305A further reduces the amount of material needed for structural support, which reduces the weight of the tile without compromising the flexural strength of the tile. For example, the embodiment of the tile 20A described above can support the same load as most standard tiles, but has an installed weight of less than 6 pounds per square foot, which is about 40% lighter than most standard tiles.

[0041] The number and structure of the ribs may vary depending on the size, aesthetic design, and intended use of the tile. Accordingly, the concepts of varying the width and length of the ribs and strategically positioning the ribs to support the tile where the flexural strength may be compromised are within the scope of this invention.

[0042] In addition to the ability of the ribs 300A to improve the flexural strength of the tiles, the secondary ribs 305A further improve certain manufacturing characteristics. As may be understood, when the tiles 20A are initially produced, they are not completely solidified, and can sag in certain instances, especially in locations that include unsupported spans. The secondary ribs 305A, if they are supported, can provide support to prevent such sagging. Therefore, the secondary ribs 305A provide support for an otherwise unsupported horizontal portion.

[0043] In addition to the ribs 300A, the lower face of the tile 20A further includes touch points 307A, 311A. Touch points 307A, 311A are protrusions that extend from the lower face of the tile 20A. In the embodiment of the tile 20A shown in FIGS. 1 through 8, upper touch points 311A are adjacent to the head end 32A, and one of the upper touch points 311A is part of the ribs 300A and one of the upper touch points 311A is separate from the ribs 300A. When tiles 20A are stacked vertically adjacent one another, such as when being shipped from the manufacturer to the job site, the upper touch points 311A of upper tile 20A seat within the upper touch surfaces 310A of lower tile 20A. This configuration prevents movement of stacked tiles relative to one another, thereby preventing adjacent tiles from scratching or damaging each other. In addition, the upper touch points 311A and upper touch surfaces 310A reduce the height of vertical stack of tiles, which allows more tiles to be included in a shipment. Furthermore, the upper touch points 311A are not visible once the tile 20A is installed, thus maintaining the simulated appearance of wood shakes.

[0044] Lower touch point 307A is positioned transverse across the nose end 33A. When a tile 20A is positioned in the next-laid horizontal course above a lower tile 20A during installation, the lower touch point 307A seats upon the lower touch surface 312A of the lower tile 20A. The lower touch point 307A and the lower touch surface 312A provide a headlap alignment guide for the roofing installers.

[0045] In other embodiments, all of the upper touch points 311A can be part of the ribs 300A, all of the upper touch points 311A can be separate from the ribs 300A, the lower touch point 307A can comprise a plurality of protrusions that seat against the lower touch surface 312A, or the tile 20A can include one or more upper touch points 311A.

[0046] To facilitate the mounting of tiles horizontally adjacent to one another, the tile 20A also includes an upwardly facing, sidewardly extending engagement member 25A and a downwardly facing, sidewardly extending engagement member 29A, as shown in FIGS. 1, 4, 7, and 8. Engagement member 25A extends to the left of the left portion 23A, defines a channel 26A, and includes an upwardly directed ledge portion 27A. Engagement member 29A extends to the right of the right portion 24A, defines a channel 31A, and includes a downwardly directed ledge portion 30A. Engagement member 25A of a first tile mates with the engagement member 29A of a second tile placed horizontally to the left of the first tile. The downwardly directed ledge portion 30A of the second tile is received by the channel 26A of the first tile. Additionally, the channel 26A serves to divert water from the first and second tiles to the tile below the first and second tiles. Similarly, engagement member 29A of the first tile mates with the engagement member 25A of a third tile placed horizontally to the right of the first tile. The upwardly directed ledge portion 27A of the third tile is received into the channel 31A of the first tile. The channel 26A of the third tile serves to divert water from the first and third tiles to the tile below the first and third tiles. As discussed below in relation to FIGS. 9 and 12, the engagement portion 29A of tile 20A can mate with an engagement portion 30B of an adjacent tile having a "B" profile configuration. Similarly, the engagement portion 30A of tile 20A can mate with an engagement portion 29B of an adjacent tile having a "B" profile. In an alternative embodiment, engagement member 25A extends from the right portion 24A and engagement member 29A extends from the left portion 23A. Thus, the embodiment of the tile described above has a Grade 1 Weathering Index of greater than 500 (see ASTM C1167-96, Table 1) due at least in part to the improved strength to weight ratio and the ability of the tile to channel water and debris.

[0047] FIGS. 9 through 16 illustrate an embodiment of a single roofing tile having a "B" profile. Like the tile 20A described above, the "B" profile tile 20B includes an upper face, a lower face, a head end 32B, a nose end 33B, and a body 36B. In addition, similar to the tile 20A, the body 36B and the nose end 33B include a simulated wood grain design and the nose end 33B further includes the gaps and shadows that are expected in a wood shake roof such that two overlapping tiles have irregular clearance, as shown in FIG. 13.

[0048] The body 36B includes a left portion 23B, a right portion 24B, and a center portion 22B. However, unlike the substantially flat upper face of tile 20A, tile 20B has a depressed center portion 22B, as shown in FIGS. 9 and 13. The head end 32B, the left portion 23B, and the right portion 24B slope downwardly towards the center portion 22B such that the head end 32B, the left portion 23B, and the right portion 24B are higher in elevation than the center portion 22B, and the depressed center portion 22B extends to the nose end 33B of the tile 20B. In addition, the left 23B and right portions 24B adjacent to the nose end 33B have a slightly higher elevation than the head end 32B, as shown in FIGS. 15 and 16.

[0049] Further, as shown in FIG. 9, the length of the 20B tile from the head end 32B to the nose end 33B varies between the left 23B and right portions 24B and the center portion 22B. In particular, the length of the center portion 22B from the head end 32B to the nose end 33B is shorter than the length of the left 23B and right portions 24B from the head end 32B to the nose end 33B. In addition, the left 23B and right portions 24B of the tile 20B extend to substantially the same length as the tile 20A, and the elevation of the left portion 23A and the right portion 24A of the tile 20A and the elevation of the left 23B and right portions 24B of the tile 20B are substantially the same. Thus, the decreased elevation and reduced length of the center portion 22B contrasted with the higher elevations and longer length of the left 23A, 23B and right portions 24A, 24B of the tile 20A and 20B creates the desired shadowing and appearance to simulate the overlapping of wood shakes. In addition, when tiles 20A are placed on either side of a tile 20B, a staggering effect is created. This staggering effect gives the impression that the center portion of the tile 20B is one tile, the left portion of the tile 20B and the tile 20A to the left of the tile 20B are one tile, and the right portion of the tile 20B and the tile 20A to the right of the tile 20B are one tile.

[0050] As shown in FIGS. 10 and 14, tile 20B further includes two transverse ridges 250B, 251B that extend across the head end 29B of tile 20B. These ridges 250B, 251B are similar to the transverse ridges 250A, 251A of the tile 20A discussed above in relation to FIG. 2. The substantially similar arrangement of the transverse ridges 250A, 250B, 251A, 251B and the lower touch surface 312A, 312B facilitates the placement of the nose end 33A, 33B of tile 20A, 20B atop the head end 32A, 32B of tile 20A, 20B during installation. Thus, tiles 20A and tiles 20B are interchangeable in the installation, which provides a more rustic appearance and better simulates the appearance of a wood shake roof.

[0051] Like the tile 20A, the tile 20B includes an upwardly facing, sidewardly extending engagement member 25B and a downwardly facing, sidewardly extending engagement member 29B, as shown in FIGS. 9, 12, 15, and 16. Engagement members 25B and 29B are configured similarly to engagement members 25A and 29A described above. In an exemplary installation in which the tile 20A is laid to the right of the tile 20B, engagement member 25A mates with the engagement member 29B. More specifically, the upwardly directed ledge portion 27A of engagement portion 25A is received into the channel 31B of adjacent engagement member 29B. Similarly, in an exemplary installation in which the tile 20A is laid to the left of the tile 20B, engagement member 29A mates with engagement member 25B. More specifically, the downwardly directed ledge portion 30A of engagement member 29A is received into the channel 26B of adjacent engagement member 25B.

[0052] As shown in FIGS. 11 and 12, the lower face of the tile 20B includes a plurality of strategically placed structural ribs 300B to provide lightweight yet structurally sound support for the tile 20B. Two edge ribs 301B extend along the length of the tile 20B, similar to the nose rib 307A and the edge ribs 301A of the tile 20A described above in relation to FIG. 4. However, the central ribs 303B and the secondary ribs 305B of the tile 20B are configured differently than the corresponding ribs 303A, 305A of the tile 20A due, at least in part, to the lower elevation of the center portion 22B and the need to support the center portion 22B and the transition areas between the center portion 22B and the left 23B and right portions 24B and head end 32B. For example, tile 20B includes two center ribs 303B that extend the full length of the tile 20B, and the two center ribs 303B increase in width under the center portion 22B of the tile 20B. In addition, three secondary ribs 305B, which are shorter than center ribs 303B, are spaced intermittently between the edge ribs 3011 and the center ribs 303B adjacent the body 36B. One of the secondary ribs 305B is positioned near the elevation transition from the left portion 23B to the center portion 22B to support the transition, and one of the secondary ribs 305B is positioned near the elevation transition from the right portion 24B to the center portion 22B. Furthermore, the center ribs 303B and the secondary ribs 305B of the tile 20B are shorter than the corresponding ribs 303A, 305A of the tile 20A because the center portion 22B of the tile 20B is shorter than the center portion 22A of tile 20A.

[0053] Furthermore, the tile 20B includes touch points 307B, 3111B that extend from the lower face of the tile 20B and engage upper touch surfaces 312B, 310B, respectively, of a tile 20B stacked below the tile 20B, such as the touch points 307A, 311A and touch surfaces 312A, 310A of tile 20A described above in relation to FIG. 3. In the embodiment illustrated in FIG. 11, two of the upper touch points 3111B are part of a rib 300B, and one of the upper touch points 3111B is separate from the ribs 300B. However, the upper touch points 3111B, like upper touch points 311A, can all be separate from the ribs 300B or can all be part of the ribs 300B. In addition, the tile 20B may include one or more touch points 307B, 3111B. Furthermore, in the embodiment shown in FIGS. 2 and 10, the touch surfaces 310A, 310B, 312A, 312B, and the touch points 311A, 3111B, 307A, 307B are in substantially similar positions, allowing the tiles 20A, 20B to be vertically stacked together or laid together in a random arrangement in each horizontal course while maintaining proper alignment of each course.

[0054] The Manufacturing Process

[0055] Reference is now made to FIGS. 17 and 18, which combine to illustrate an exemplary method of manufacturing tiles using raw, unmolded clay material to produce two similar tile forms suitable for kiln firing. A rotating mold 10 accepts clay bats 13 and forms them into tile shapes, such as those shapes described above. After being dried and kiln fired, these tiles can be installed in an overlapping manner as shown in FIG. 19 atop an inclined support surface, such as support surface 43.

[0056] A clay composition is extruded from a pugmill/extrusion machine in a column (not shown) and has a moisture content sufficient to provide adequate plasticity. The percentage of moisture content found to be acceptable in one embodiment is 17 to 19%. The extrusion process evacuates substantially all of the air from the clay mixture to discourage delamination. The column is then cut into short lengths to create the bats 13 for pressing.

[0057] The press structure includes a rotating drum 10 having a hexagonal cross-section and defining six outwardly directed drum faces. One "A" lower mold cavity 11A and one "B" lower mold cavity 11B are provided on each drum face, totaling twelve mold cavities, to provide an aesthetically pleasing variation on the installed appearance of the tiles, which is discussed above in relation to FIGS. 1 and 9. The net result is a 50--50 mix of tiles having an "A" profile and tiles having a "B" profile, such as those tiles 20A and 20B discussed above.

[0058] As shown in FIG. 18, the clay bats 13 enter the press and are deposited in the lower molds 11A, 11B when the molds 11A, 11B are in the 10 o'clock position. The drum 10 is configured to rotate about a substantially horizontal axis, such that upon drum rotation, the bats 13 are moved into the 12 o'clock position. While in the 12 o'clock position, a top mold member 14 comes down and presses the bats 13 into the shapes of the tiles 20, and then withdraws upwardly. The drum 10 then rotates the pressed tile forms 20 to the 2 o'clock position, where a vacuum picker (not shown) moves in and simultaneously trims off the excess clay around the edges of the tiles 20 and punches nail holes as needed. It removes the tiles 20 from the drum face and deposits them on drying trays (not shown) that are passed under the picker on a synchronized conveyor.

[0059] The wet tiles, on their individual dryer trays, are then sent through a dryer where the moisture content is reduced to less than 4%. The dry "greenware" is then transported to the kiln for firing. The vitrified tiles 20A, 20B, as shown in FIGS. 1 and 9, are then placed directly into their shipping pallets. The combination of the touch points 311A, 311B and the transverse ridges 250A, 250B, 251A, 251B allows the tiles 20A, 20B to be stacked vertically relative to each other while preventing the tiles 20A, 20B from moving relative to each other, which prevents chipping and scratching of tiles 20A, 20B during shipping.

[0060] Furthermore, because tiles composed of clay may shrink when drying, tiles according to one embodiment of the invention are dimensioned to optimize the strength to weight ratio. The optimized dimensions allow the tiles to be manufactured with more tolerance for distortion while continuing to meet building code specifications for weight.

[0061] The Installation Process

[0062] Reference is now made to FIGS. 19 through 21, which combine to illustrate the tile installation process according to the present invention. The tiles 20A, 20B are typically installed horizontally in interlocked courses, with each horizontal course overlapping the one immediately below it. The overlap is typically about 2.25 inches, although other overlap lengths are contemplated without departing from the spirit and scope of the present invention. The lower ridge 251A, 251B and the adjacent lower touch surface 312A, 312B facilitate the proper alignment of the next-laid course. In addition, the ribs 300A, 300B extending from an upper tile 20A, 20B have a level resting surface on the lower ridge 251A, 251B of a lower tile 20A, 20B when installed, and the touch point 307A, 307B of the upper tile 20A, 20B seats on the lower touch surface 312A, 312B of the lower tile 20A, 20B. Additionally, having the ribs 300A, 300B of the upper tile 20A, 20B resting on the lower ridge 251A, 251B directs water to the exposed surface of the tile 20A, 20B below it, thus preventing the water from backing up behind the lower tile 20A, 20B.

[0063] The tiles are attached to a supporting surface 43 (such as plywood) by nails or other suitable fasteners engaged into apertures 260A, 260B, 261A, 261B. A common eave-riser metal drip edge 42 is used at the bottom of the roof to support the bottom horizontal course of tiles 20A, 20B.

[0064] As is shown in FIG. 20, the edge portions 35 of the tiles 20A, 20B are offset from the edge portions 35 of the tiles 20A, 20B below them to facilitate the diversion of water and debris. To size tiles 20A, 20B such that the edge portions 35 can be offset from those tiles 20A, 20B below them, installers may need to cut a tile 20A, 20B lengthwise. In one embodiment, the installers can cut between the two center primary ribs 303B for tile 20B or between the center primary rib 303A and one of the secondary ribs 305A for the tile 20A. The rib design provides flexibility as to where the tiles 20A, 20B may be cut, which results in faster installation without compromising too much strength.

[0065] In an alternative embodiment (not shown), hip trim tiles are provided in varying widths. The hip trim tiles are used along the edge of the roof leading up to the ridge of the roof. Two configurations of hip trim tiles may be used according to one embodiment, a "C" configuration and a "D" configuration, wherein the "C" configuration hip trim tile has a width that is less than the width of the "D" configuration hip trim tile. Alternating the use of the "C" configuration hip trim tile and the "D" configuration hip trim tile with each horizontal course will result in the edge portions 35 of each course being offset from the course below or above it. The number of hip trim tile configurations may be greater than two, depending on the needs of the installation.

[0066] In addition to including hip trip tiles, one embodiment of the tiling system further includes hip trim starter tiles and ridge trim tiles. Hip trim starter tiles are used on the bottom course at the bottom corners of the roof. The hip trim starter tiles provide a clean finish for the bottom corners of the roof. Ridge trim tiles are installed along the ridge of the roof and overlap the horizontal course of tiles below them.

CONCLUSION

[0067] Therefore it may be seen that the present invention overcomes deficiencies in the prior art by providing roofing tiles which can be produced in mass quantities, yet have the appearance of traditional wood shakes with the structural properties of fired clay. In addition, by having one or more structural support ribs, the tiles have the strength of standard tiles, but weigh significantly less than standard tiles. Furthermore, the present invention provides touch points on each tile that engage receiving portions on a vertically adjacent tile for preventing the relative movement of tiles. While this invention has been described in specific detail with reference to the disclosed embodiments, it will be understood that many variations and modifications may be affected within the spirit and scope of the invention as described in the appended claims.