ROOF TILE
United States Patent 3862532
A one-piece molded plastic tile of rectangular shape is provided at its upper and lower ends and at each side with means enabling its interlocking engagement with not only the adjoining tiles of its course, but also with means on both its upper and lower ends for interlocking engagement with all upper and lower course tiles which bound it. In addition, the tile is equipped with nailing tabs by which it may be secured to an underlying roof sheathing, the tabs being so constructed and arranged that, when nailed to a roof sheathing, they not only hold the tile securely attached to the sheathing, but also provide a three-point anchorage which prevents any angular movement of the tile relative to the roof sheathing.
US Patent References:
Roof construction
Fall - June 1935 - 2004198
Roofing tile
Bremer - September 1949 - 2482835
Roofing tile
Pretty - June 1950 - 2510416
Shingles
Ball - October 1957 - 2811118
ROOFING TILE
Greenleaf - May 1971 - 3579940
Roof construction
Fall - June 1935 - 2004198
Roofing tile
Bremer - September 1949 - 2482835
Roofing tile
Pretty - June 1950 - 2510416
Shingles
Ball - October 1957 - 2811118
ROOFING TILE
Greenleaf - May 1971 - 3579940
Application Number:
05/339271
Publication Date:
01/28/1975
Filing Date:
03/08/1973
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
52/553, 52/536
International Classes:
E04D1/08; E04D3/32; E04D1/02; E04D3/24; E04D3/32; E04D1/20
Field of Search:
52/521,536,538,553,533,538
US Patent References:
| 3686813 | WALL COVERING DEFINING A CONTINUOUS VENTILATING CONDUIT | August 1972 | Breitwieser et al. |
Primary Examiner:
Perham, Alfred C.
Attorney, Agent or Firm:
Dennison, Dennison, Townshend & Meserole
Claims:
I claim
1. A one-piece plastic material roof tile comprising: a planar sheet body of rectangular configuration having a lower end wall depending therefrom, an upper end wall depending therefrom and of a less height than the lower end wall; a pair of laterally spaced parallel channels formed in the tile body parallel to and laterally outwardly from one side thereof between the upper and lower end walls and being open at both ends; the tile body having a side wall adjacent said channels having throughout its length and intermediate its top and bottom edges a lateral flange extending outwardly from said wall and constituting a bottom common to both channels, which bottom lies in a plane parallel to and spaced above a plane common to the bottom edges of the side wall and thereby provides an air space beneath and coextensive with said channels; the outer side wall of the outer channel depending from said bottom flange at a point closer to the lower end of the tile than its upper end and terminating in an outwardly extending foot flange constituted as a nailing tab offset below the bottom edge of the outermost channel side wall; the other side of the tile body having a laterally outward marginal extension of the planar sheet body provided with a depending connector flange constructed and arranged for interlocking seating engagement in the outer channel of an identical tile if and when interlocked therewith in service; the inner one of said pair of parallel channels being open at its top through its length when in service position; the marginal portion of the lower end wall adjacent said marginal extension being inwardly offset to provide a recess open to that side edge of the tile; said lower end wall at the channeled side of the tile having a longitudinal extension exactly complemental to said recess; intermediate support ribs depending from the tile body in parallel spaced relation between the upper and lower end walls and together with said side wall having longitudinally alternate solid portions and ventilation apertures open to their bottom edges; said channel common bottom flange projecting outwardly beyond the upper end wall of the tile and downwardly offset relative to the bottom edge of said upper end wall and constituted as a second nailing tab disposed in a plane common to the first-named nailing tab; the bottom edges of the solid portions of the support ribs and side wall lying also in said plane common to the first and second nailing tabs, whereby the bottom edges of the upper and lower end walls of the tile will at all times be spaced above any surface on which the tile is mounted in service position; and a third nailing tab extending from the tile body flush with the bottom edge of its upper end wall in longitudinal alignment with said interlocking connector flange.
1. A one-piece plastic material roof tile comprising: a planar sheet body of rectangular configuration having a lower end wall depending therefrom, an upper end wall depending therefrom and of a less height than the lower end wall; a pair of laterally spaced parallel channels formed in the tile body parallel to and laterally outwardly from one side thereof between the upper and lower end walls and being open at both ends; the tile body having a side wall adjacent said channels having throughout its length and intermediate its top and bottom edges a lateral flange extending outwardly from said wall and constituting a bottom common to both channels, which bottom lies in a plane parallel to and spaced above a plane common to the bottom edges of the side wall and thereby provides an air space beneath and coextensive with said channels; the outer side wall of the outer channel depending from said bottom flange at a point closer to the lower end of the tile than its upper end and terminating in an outwardly extending foot flange constituted as a nailing tab offset below the bottom edge of the outermost channel side wall; the other side of the tile body having a laterally outward marginal extension of the planar sheet body provided with a depending connector flange constructed and arranged for interlocking seating engagement in the outer channel of an identical tile if and when interlocked therewith in service; the inner one of said pair of parallel channels being open at its top through its length when in service position; the marginal portion of the lower end wall adjacent said marginal extension being inwardly offset to provide a recess open to that side edge of the tile; said lower end wall at the channeled side of the tile having a longitudinal extension exactly complemental to said recess; intermediate support ribs depending from the tile body in parallel spaced relation between the upper and lower end walls and together with said side wall having longitudinally alternate solid portions and ventilation apertures open to their bottom edges; said channel common bottom flange projecting outwardly beyond the upper end wall of the tile and downwardly offset relative to the bottom edge of said upper end wall and constituted as a second nailing tab disposed in a plane common to the first-named nailing tab; the bottom edges of the solid portions of the support ribs and side wall lying also in said plane common to the first and second nailing tabs, whereby the bottom edges of the upper and lower end walls of the tile will at all times be spaced above any surface on which the tile is mounted in service position; and a third nailing tab extending from the tile body flush with the bottom edge of its upper end wall in longitudinal alignment with said interlocking connector flange.
Description:
BACKGROUND
The field of the present invention is the art of roof tiling of the shingle type, and in particular to one-piece tiles of molded plastic material.
The prior art in this field is old and crowded. Perhaps its closest approach to the present invention is found in the teaching of U.S. Pat. Nos. 973,946; 2,811,118; and 3,412,517. These patents are fairly representative of the state of the prior art. They, and the bulk of the prior art, teach that adjoining tiles of a course may be interlocked at their adjacent side edges, and that individual tiles may be provided with nailing tabs by which they may be attached to an underlying roof structure, but they provide no solution to the problem of how to keep shingle type tiles from being blown off a roof to which they are attached, or becoming loosened to an extent which permits water seepage or direct leakage onto the underlying roof structure. Although the prior art recognizes the problem of procuring adequate ventilation of the roof structure that underlies the tiles, it has no simple, inexpensive solution.
SUMMARY OF THE INVENTION
The present invention is a shingle type roof tile of rectangular configuration so constructed and arranged that when it is in service position on a roof sheathing, it is not only securely fastened to the sheathing, but is also so interlocked with the adjoining side and upper and lower course tiles which border it that it cannot be separated from its bordering tiles or be otherwise dislodged by wind force, and is leak proof. Furthermore, each tile is secured to each adjoining tile in the same course by at least two fasteners common thereto and which serve also to attach the tiles to their underlying roof structure. In addition, the fasteners serve also to prevent any shifting or angular movement of the tiles relative to a roof structure to which they are attached.
DESCRIPTION OF DRAWINGS
FIG. 1 is a fragmentary perspective view of a roof tile installation using tiles of the present invention.
FIG. 2 is a sectional view taken on line 2--2 of FIG. 1.
FIG. 3 is an enlarged fragmentary section of the tile joint at the middle of FIG. 2 and also on the line 2--2 of FIG. 1.
FIG. 4 is a top plan view of the roof tile of the present invention.
FIG. 5 is a lower end elevation of the tile as viewed from the bottom of FIG. 4.
FIG. 6 is an upper end elevation of the tile.
FIG. 7 is a sectional view on line 7--7 of FIG. 4.
FIG. 8 is a sectional view on line 8--8 of FIG. 4.
FIG. 9 is a sectional view on line 9--9 of FIG. 4.
DETAILED DESCRIPTION
The tile of the present invention is a one-piece rectangular body of molded plastic constituted as a sheet having a flat face 10 terminating at the lower end of the tile in a depending flange 11 and terminating at the upper end of the tile in a depending flange 12 that is parallel to but of less height than the flange 11, as best seen in FIG. 7. The outer face of the lower end flange 11 is formed with a supplemental lateral flange 13 coextensive in length with the flange 11 and flared outwardly and downwardly relative thereto. The outer face of the upper end flange 12 is formed with a lateral outward extension 14 coextensive in length with the flange 12 and having a flat underface that is spaced slightly above and parallel to a conventional roof sheathing 15 when the tile is in service position as illustrated in FIG. 1. The flange 14 projects somewhat outwardly beyond the upper end edge of the tile face 10 and provides a bottom of a dovetail undercut 16 in the outer face of the flange 12. The undercut makes the outer face of the flange 12 a female dovetail for receiving a complemental male dovetail member on the outer face of the lower end flange of the next following upper course of tiles. One such male dovetail member is shown at 17 in FIG. 1, its bottom face being flush with the bottom edge of the flange 11 and in the plane of the upper face of the extension 14 of the flange 12.
As best shown in FIG. 2, the tile is provided at its side edge portions with side walls constituted as parallel depending flanges 18 and 19 perpendicular to the sheet portion 10. The right side wall 18 extends in its entirety between the upper and lower ends of the tile with longitudinally spaced portions of its bottom edge seating flatly on the surface of the roof sheathing 15. Because of the fact that the lower end of the tile sheet portion 10 is elevated above the roof sheathing 15 to a greater extent than its upper end, the outer face portion 10 of the tile and the bottom edge portions of the side walls 18 and 19 lie in respective planes that are divergent from the upper to the lower end of the tile, as shown in FIGS. 7-9.
A lateral flange 20 extends outwardly from the wall flange 18 and parallel to the plane of the bottom edges of the side wall 18 as shown in FIG. 8 and spaced thereabove. It carries a pair of upstanding walls 21 and 22 in parallel laterally spaced relation to each other and to the side wall 18. The top edges of these walls occupy a plane that is common to the plane of the underface of the tile portion 10. The walls 21 and 22 in cooperation with the adjacent side wall 18 provide a pair of open top channels 23 and 24, respectively, which extend from the upper to the lower end of the tile and which are open at each end. At their lower ends, the walls 21 and 22 lie in a plane common to the plane of the lower end flange 11 of the tile. The lower end of the outermost wall 22 is formed with an outwardly directed lateral flange 25 perpendicular thereto and which also lies in a plane common to the plane of the tile lower end flange 11, its function being to provide an overlap to cover and protect the joint between its tile and the next adjoining one.
The other side wall 19 of the tile, like the side wall 18, seats on the surface of the roof sheathing 15. Its upper end is located laterally inward from the adjacent side edge 26 of the tile sheet 10. The marginal portion of sheet 10 between its edge 26 and its junction with the side wall flange 19 carries a depending flange 27 which enters and seats in the channel 24 of the next adjoining tile completely filling it in a snug fit, as best shown in FIG. 3. This figure also shows clearly that when the adjoining tiles of a course are coupled, the marginal portion of the sheet 10 between its edge 26 and the top of the side wall 19 overlies and seats upon the top of the adjoining channel wall flanges 21 and 22, leaving the inner channel 23 open at its top throughout its full length.
It will be noted in FIG. 4 that the shield 13 on the lower end flange 11 of the tile extends horizontally across the face of the flange over the entire distance between the location of the side wall flange 19 and the outer edge of the overlap 25. This arrangement provides a recess 28 at the lower left corner of the tile for receiving and nesting the overlap 25 of the next adjoining tile when the tiles are interlocked in service position.
A feature of the present invention is the location and arrangement of nail tabs for attaching the tile in service position on the roof sheathing. As here illustrated, there are three tabs, 29, 30, and 31. the tab 29 is a small lateral foot flange extending outwardly from the lower end of a portion 32 of the outer channel wall 22 which depends below the flange 20 that constitutes the floor of the channels 23 and 24. Preferably, the nail tab 29 is closer to the lower end of the tile than to its upper end, thus providing three-point resistance to any forces tending to effect angular displacement of the tile after it is secured in service position. The tab 30, hereinafter called the underlapping tab, is located at the upper right corner of the tile as a longitudinal extension of the floor flange 20 of the channels 23 and 24. As shown in FIGS. 8 and 9, the tab 30 is offset downwardly from the channel floor flange 20 and projects beyond the edge of the upper end of the tile. The tab 31, hereinafter called the overlapping tab, is located at the upper left corner of the tile and, as best shown in FIG. 7, projects beyond the upper end edge thereof to the same extent as does the tab 30. It is offset downwardly from the plane of the tile sheet 10 but at a level above the level of tab 30, as shown in FIGS. 8 and 9. All the tabs have holes for nails or other suitable fastening elements by which the tiles are secured to the roof sheathing 15.
The under face of the tile sheet portion 10 has depending therefrom a plurality of support ribs 33 in laterally spaced relation and parallel to the tile side walls 18 and 19. In the embodiment of the invention here shown, these ribs 33 and also the walls 18 and 19 are panels that extend between the upper and lower end flanges of the tile, and all are deeply serrated to provide in each a plurality of cross ventilation apertures 34 open to their bottom edges. The bottom edges 35 of the solid portions of the panels and side walls lie in a plane that is common to the plane of the under faces of the nail tabs 29 and 30. It is preferred that each support rib panel 33 be aligned with a male dovetail member 17, so that the dovetail member is reinforced.
As best shown in FIGS. 5 and 6, each panel comprised of the ribs 33 and the side walls 18 and 19 is of such height at its upper and lower ends that it maintains the respective bottom edges of the front and rear walls 11 and 12 spaced above a roof sheathing on which the tile is set when in service position. Furthermore, when successive upper courses of tiles are set as shown in FIG. 1, the bottom edge of each higher course lower end wall 11 will be spaced above the top face of the sheet 10 of the adjacent lower course. In consequence, air will at all times circulate freely beneath all tiles of a roof assembly, flowing continuously upward from bottom to top of the roof and, because of the lateral communication between the air spaces of all tiles provided by their ventilation apertures 34, flowing continuously transversely through and from adjoining tiles from end to end of the roof. There is no space beneath any tile in an entire roof assembly in which air can be trapped.
OPERATION
The tiles of each course are interlocked at each side simply by seating the depending flange 27 on the left side of each in the outer channel 24 at the right side of its adjoining tile as shown in FIGS. 2 and 3, with its lower end flush with the overlap member 25; it being understood that the tab 29 has first been nailed to the roof sheathing 15. This is a simple vertical seating action requiring no appreciable longitudinal movement of the tile being placed. When so positioned, the overlapping tab 31 of the tile being placed will seat on the underlapping tab 30 of the fixed tile with the nail holes of both tabs in registry. Both tabs are then secured to the roof sheathing by a single nail passed through the registering holes, whereupon the tile being placed will be anchored in service position and becomes a fixed tile. This operation is repeated in succession for each tile in the course. When the next higher course of tiles is laid to overlap the upper end of the first course, the male dovetail members 17 of the higher course will seat in the female dovetail 14 of the lower course and the joint thus made will be covered by the overlying shield 13 on the lower end flange 11 of the upper course. The joint of the mating dovetails is held down by the shield 13 so that the lower end of the upper course cannot be lifted vertically way from its firm face contact with the underlying upper end portion of the lower course, and the shield functions additionally as a watershed that inhibits passage or seepage of water into the space beneath the tile sheet portion 10. This operation is repeated for each successively higher course.
Referring to FIGS. 1, 2 and 3, it will be apparent that the open top channel 23 of each tile provides quick drainage for water shed from the upper tile courses, so that the water can never back up and accumulate in puddles that may, if not drained, seep down onto the roof sheathing 15 and thus ultimately enter the building space beneath the sheathing. Water in the drainage channel 23 escapes through its open lower end. The marginal portion of the tile sheet portion 10 between the channel 24 (see FIG. 3) and the side edge 26 of each tile normally covers the channel 24 which houses the interlocking flange 27 of the next adjoining tile and thus inhibits any direct flow of water into the channel. If, however, due to moisture precipitation or any other cause, water should accumulate in the channel 24, it will drain from the lower end of the channel through a seep hole 36 in the floor flange 20 of the channel at its lower end, shown in the lower right corner of FIG. 4, and will fall onto the upper end portion of the tile in the next lower course.
It will be apparent from the foregoing description that each individual tile in all course above the lowermost is interlocked with each of the six tiles which bound it; that is, the two adjoining tiles in its course, the two adjoining tiles of the upper course which overlap its upper end, and the two adjoining tiles in the lower course which its lower end portion overlaps.
Because of the fact that the nail tabs 29 and 30 are downwardly offset with their under faces in a plane common to the bottom edges of the side walls 18 and 19 and the bottom edges 35 of the support ribs, there is always ample ventilation space between the tile sheet 10 and the roof sheathing, both longitudinally and transversely of each tile in each course. The air path is continuous and constantly rising through the lowest to the highest course.
The field of the present invention is the art of roof tiling of the shingle type, and in particular to one-piece tiles of molded plastic material.
The prior art in this field is old and crowded. Perhaps its closest approach to the present invention is found in the teaching of U.S. Pat. Nos. 973,946; 2,811,118; and 3,412,517. These patents are fairly representative of the state of the prior art. They, and the bulk of the prior art, teach that adjoining tiles of a course may be interlocked at their adjacent side edges, and that individual tiles may be provided with nailing tabs by which they may be attached to an underlying roof structure, but they provide no solution to the problem of how to keep shingle type tiles from being blown off a roof to which they are attached, or becoming loosened to an extent which permits water seepage or direct leakage onto the underlying roof structure. Although the prior art recognizes the problem of procuring adequate ventilation of the roof structure that underlies the tiles, it has no simple, inexpensive solution.
SUMMARY OF THE INVENTION
The present invention is a shingle type roof tile of rectangular configuration so constructed and arranged that when it is in service position on a roof sheathing, it is not only securely fastened to the sheathing, but is also so interlocked with the adjoining side and upper and lower course tiles which border it that it cannot be separated from its bordering tiles or be otherwise dislodged by wind force, and is leak proof. Furthermore, each tile is secured to each adjoining tile in the same course by at least two fasteners common thereto and which serve also to attach the tiles to their underlying roof structure. In addition, the fasteners serve also to prevent any shifting or angular movement of the tiles relative to a roof structure to which they are attached.
DESCRIPTION OF DRAWINGS
FIG. 1 is a fragmentary perspective view of a roof tile installation using tiles of the present invention.
FIG. 2 is a sectional view taken on line 2--2 of FIG. 1.
FIG. 3 is an enlarged fragmentary section of the tile joint at the middle of FIG. 2 and also on the line 2--2 of FIG. 1.
FIG. 4 is a top plan view of the roof tile of the present invention.
FIG. 5 is a lower end elevation of the tile as viewed from the bottom of FIG. 4.
FIG. 6 is an upper end elevation of the tile.
FIG. 7 is a sectional view on line 7--7 of FIG. 4.
FIG. 8 is a sectional view on line 8--8 of FIG. 4.
FIG. 9 is a sectional view on line 9--9 of FIG. 4.
DETAILED DESCRIPTION
The tile of the present invention is a one-piece rectangular body of molded plastic constituted as a sheet having a flat face 10 terminating at the lower end of the tile in a depending flange 11 and terminating at the upper end of the tile in a depending flange 12 that is parallel to but of less height than the flange 11, as best seen in FIG. 7. The outer face of the lower end flange 11 is formed with a supplemental lateral flange 13 coextensive in length with the flange 11 and flared outwardly and downwardly relative thereto. The outer face of the upper end flange 12 is formed with a lateral outward extension 14 coextensive in length with the flange 12 and having a flat underface that is spaced slightly above and parallel to a conventional roof sheathing 15 when the tile is in service position as illustrated in FIG. 1. The flange 14 projects somewhat outwardly beyond the upper end edge of the tile face 10 and provides a bottom of a dovetail undercut 16 in the outer face of the flange 12. The undercut makes the outer face of the flange 12 a female dovetail for receiving a complemental male dovetail member on the outer face of the lower end flange of the next following upper course of tiles. One such male dovetail member is shown at 17 in FIG. 1, its bottom face being flush with the bottom edge of the flange 11 and in the plane of the upper face of the extension 14 of the flange 12.
As best shown in FIG. 2, the tile is provided at its side edge portions with side walls constituted as parallel depending flanges 18 and 19 perpendicular to the sheet portion 10. The right side wall 18 extends in its entirety between the upper and lower ends of the tile with longitudinally spaced portions of its bottom edge seating flatly on the surface of the roof sheathing 15. Because of the fact that the lower end of the tile sheet portion 10 is elevated above the roof sheathing 15 to a greater extent than its upper end, the outer face portion 10 of the tile and the bottom edge portions of the side walls 18 and 19 lie in respective planes that are divergent from the upper to the lower end of the tile, as shown in FIGS. 7-9.
A lateral flange 20 extends outwardly from the wall flange 18 and parallel to the plane of the bottom edges of the side wall 18 as shown in FIG. 8 and spaced thereabove. It carries a pair of upstanding walls 21 and 22 in parallel laterally spaced relation to each other and to the side wall 18. The top edges of these walls occupy a plane that is common to the plane of the underface of the tile portion 10. The walls 21 and 22 in cooperation with the adjacent side wall 18 provide a pair of open top channels 23 and 24, respectively, which extend from the upper to the lower end of the tile and which are open at each end. At their lower ends, the walls 21 and 22 lie in a plane common to the plane of the lower end flange 11 of the tile. The lower end of the outermost wall 22 is formed with an outwardly directed lateral flange 25 perpendicular thereto and which also lies in a plane common to the plane of the tile lower end flange 11, its function being to provide an overlap to cover and protect the joint between its tile and the next adjoining one.
The other side wall 19 of the tile, like the side wall 18, seats on the surface of the roof sheathing 15. Its upper end is located laterally inward from the adjacent side edge 26 of the tile sheet 10. The marginal portion of sheet 10 between its edge 26 and its junction with the side wall flange 19 carries a depending flange 27 which enters and seats in the channel 24 of the next adjoining tile completely filling it in a snug fit, as best shown in FIG. 3. This figure also shows clearly that when the adjoining tiles of a course are coupled, the marginal portion of the sheet 10 between its edge 26 and the top of the side wall 19 overlies and seats upon the top of the adjoining channel wall flanges 21 and 22, leaving the inner channel 23 open at its top throughout its full length.
It will be noted in FIG. 4 that the shield 13 on the lower end flange 11 of the tile extends horizontally across the face of the flange over the entire distance between the location of the side wall flange 19 and the outer edge of the overlap 25. This arrangement provides a recess 28 at the lower left corner of the tile for receiving and nesting the overlap 25 of the next adjoining tile when the tiles are interlocked in service position.
A feature of the present invention is the location and arrangement of nail tabs for attaching the tile in service position on the roof sheathing. As here illustrated, there are three tabs, 29, 30, and 31. the tab 29 is a small lateral foot flange extending outwardly from the lower end of a portion 32 of the outer channel wall 22 which depends below the flange 20 that constitutes the floor of the channels 23 and 24. Preferably, the nail tab 29 is closer to the lower end of the tile than to its upper end, thus providing three-point resistance to any forces tending to effect angular displacement of the tile after it is secured in service position. The tab 30, hereinafter called the underlapping tab, is located at the upper right corner of the tile as a longitudinal extension of the floor flange 20 of the channels 23 and 24. As shown in FIGS. 8 and 9, the tab 30 is offset downwardly from the channel floor flange 20 and projects beyond the edge of the upper end of the tile. The tab 31, hereinafter called the overlapping tab, is located at the upper left corner of the tile and, as best shown in FIG. 7, projects beyond the upper end edge thereof to the same extent as does the tab 30. It is offset downwardly from the plane of the tile sheet 10 but at a level above the level of tab 30, as shown in FIGS. 8 and 9. All the tabs have holes for nails or other suitable fastening elements by which the tiles are secured to the roof sheathing 15.
The under face of the tile sheet portion 10 has depending therefrom a plurality of support ribs 33 in laterally spaced relation and parallel to the tile side walls 18 and 19. In the embodiment of the invention here shown, these ribs 33 and also the walls 18 and 19 are panels that extend between the upper and lower end flanges of the tile, and all are deeply serrated to provide in each a plurality of cross ventilation apertures 34 open to their bottom edges. The bottom edges 35 of the solid portions of the panels and side walls lie in a plane that is common to the plane of the under faces of the nail tabs 29 and 30. It is preferred that each support rib panel 33 be aligned with a male dovetail member 17, so that the dovetail member is reinforced.
As best shown in FIGS. 5 and 6, each panel comprised of the ribs 33 and the side walls 18 and 19 is of such height at its upper and lower ends that it maintains the respective bottom edges of the front and rear walls 11 and 12 spaced above a roof sheathing on which the tile is set when in service position. Furthermore, when successive upper courses of tiles are set as shown in FIG. 1, the bottom edge of each higher course lower end wall 11 will be spaced above the top face of the sheet 10 of the adjacent lower course. In consequence, air will at all times circulate freely beneath all tiles of a roof assembly, flowing continuously upward from bottom to top of the roof and, because of the lateral communication between the air spaces of all tiles provided by their ventilation apertures 34, flowing continuously transversely through and from adjoining tiles from end to end of the roof. There is no space beneath any tile in an entire roof assembly in which air can be trapped.
OPERATION
The tiles of each course are interlocked at each side simply by seating the depending flange 27 on the left side of each in the outer channel 24 at the right side of its adjoining tile as shown in FIGS. 2 and 3, with its lower end flush with the overlap member 25; it being understood that the tab 29 has first been nailed to the roof sheathing 15. This is a simple vertical seating action requiring no appreciable longitudinal movement of the tile being placed. When so positioned, the overlapping tab 31 of the tile being placed will seat on the underlapping tab 30 of the fixed tile with the nail holes of both tabs in registry. Both tabs are then secured to the roof sheathing by a single nail passed through the registering holes, whereupon the tile being placed will be anchored in service position and becomes a fixed tile. This operation is repeated in succession for each tile in the course. When the next higher course of tiles is laid to overlap the upper end of the first course, the male dovetail members 17 of the higher course will seat in the female dovetail 14 of the lower course and the joint thus made will be covered by the overlying shield 13 on the lower end flange 11 of the upper course. The joint of the mating dovetails is held down by the shield 13 so that the lower end of the upper course cannot be lifted vertically way from its firm face contact with the underlying upper end portion of the lower course, and the shield functions additionally as a watershed that inhibits passage or seepage of water into the space beneath the tile sheet portion 10. This operation is repeated for each successively higher course.
Referring to FIGS. 1, 2 and 3, it will be apparent that the open top channel 23 of each tile provides quick drainage for water shed from the upper tile courses, so that the water can never back up and accumulate in puddles that may, if not drained, seep down onto the roof sheathing 15 and thus ultimately enter the building space beneath the sheathing. Water in the drainage channel 23 escapes through its open lower end. The marginal portion of the tile sheet portion 10 between the channel 24 (see FIG. 3) and the side edge 26 of each tile normally covers the channel 24 which houses the interlocking flange 27 of the next adjoining tile and thus inhibits any direct flow of water into the channel. If, however, due to moisture precipitation or any other cause, water should accumulate in the channel 24, it will drain from the lower end of the channel through a seep hole 36 in the floor flange 20 of the channel at its lower end, shown in the lower right corner of FIG. 4, and will fall onto the upper end portion of the tile in the next lower course.
It will be apparent from the foregoing description that each individual tile in all course above the lowermost is interlocked with each of the six tiles which bound it; that is, the two adjoining tiles in its course, the two adjoining tiles of the upper course which overlap its upper end, and the two adjoining tiles in the lower course which its lower end portion overlaps.
Because of the fact that the nail tabs 29 and 30 are downwardly offset with their under faces in a plane common to the bottom edges of the side walls 18 and 19 and the bottom edges 35 of the support ribs, there is always ample ventilation space between the tile sheet 10 and the roof sheathing, both longitudinally and transversely of each tile in each course. The air path is continuous and constantly rising through the lowest to the highest course.