The present invention is concerned with roofing tiles.

A problem often experienced with roofing tiles is securing of adjacent tiles so as to provide optimum weatherproof properties of the assembled tiles. I have now developed a roofing tile which alleviates the above problem.

According to the present invention there is provided a roofing tile having longitudinal and lateral edge portions, wherein at least one corrugated edge surface defines a sawtooth configuration having successive peaks and troughs in which the peaks are spaced from one another in the respective longitudinal or lateral direction, said corrugated edge surface being capable of interlocking a complementary corrugated edge surface provided on an adjacent similar tile.

It is preferred that the corrugated edge surface comprises a plurality of rows of teeth, each row advantageously substantially extending between opposed edges of the tile. Preferably the rows are substantially parallel.

Advantageously each tile comprises opposed first and second corrugated edge surfaces, wherein the peaks of the first corrugated surface stand proud of a first major face of the tile, and the peaks of the second corrugated surface stand proud of a second major face of the tile.

The corrugated surfaces are advantageously complementarily engageable with corresponding surface formations of an adjacent tile. In use the first and second corrugated surfaces are arranged along the upper and lower edges of a tile.

The tile may be provided with further corrugated edge surfaces arranged at opposed third and fourth edge portions of the tile, each further corrugated edge surface comprising a saw-tooth arrangement substantially as hereinbefore described. The peaks of the respective further corrugated edge surfaces may be arranged to protrude from opposed faces of the tile as described with reference to the first mentioned corrugated surfaces; alternatively the peaks may be arranged to protrude from a common face of the tile.

In use, the further corrugated edge surfaces are arranged along the side edges of the tiles.

The provision of corrugated edge surfaces around substantially the entire tile periphery as described above is advantageous in achieving interlocking seal areas at all edge portions of the tile. The advantage of the above arrangement can be seen when the tiles are assembled side by side in courses, with interlocking overlaps between adjacent tiles. The arrangement optimises the weatheφroof properties of the assembled tiles. A further advantage is the avoidance of the need to use securing clips or the like between adjacent tiles.

In a particularly preferred embodiment the tile further comprises a first fixing aperture, slot or knockout, arranged at a first lateral edge location of the tile, and a second fixing aperture, slot or knockout arranged, offset to the first fixing aperture, slot or knockout, at a second longitudinal edge location of the tile. The offset arrangement is advantageously such that first securing means can pass through the first fixing aperture, slot or knockout of the tile and through a second fixing aperture, slot or knockout in an adjacent overlying tile, and second securing means can pass through the second fixing aperture, slot or knockout of the tile and a first fixing aperture, slot or knockout in an adjacent underlying tile.

In the case where a knockout rather than a full aperture is provided, the tile is thinned locally in the fixing area in such a way that an aperture can be readily produced typically by punching, drilling or other mechanical methods on site.

It is preferred that the edge locations are respectively provided proximal adjacent edges of the tile. In the case where the tile is of a substantially square or rectangular shape, the adjacent edges typically define a substantially "L" shaped boundary. Preferably the edge locations are provided proximal the free ends of the "L" boundary.

The above-described arrangement of edge locations for the tile fixing apertures, slots or knockouts enables the number of securing means required to secure an overlapping assembly of such tiles to be substantially lessened. It is further preferred that the arrangement of the edge locations is such, as to allow the tiles to be arranged in a substantially regular array, with the fixing apertures, slots or knockouts of adjacent overlying tiles being substantially aligned so as to allow a single securing means to pass therethrough.

The securing means typically comprise nails or the like, capable of attaching the tiles to a support surface.

It is preferred that the tile includes a first slot and a second offset aperture.

It is further preferred that the first fixing aperture, slot or knockout is surrounded with a collar member arranged to stand proud of the first major face of the tile. The provision of a proud collar member is advantageous for obviating water leakage through the first fixing aperture, slot or knockout. Preferably the collar member surrounds a recess portion, typically a longitudinally extending channel, in which the first fixing aperture, slot or knockout is disposed.

Advantageously the second fixing aperture, slot or knockout is similarly provided with a second collar member therearound. Typically the second collar member is arranged to stand proud of the second major face of the tile, and is preferably shaped and dimensioned to be snugly received within the recess portion of a first collar member of an adjacent tile.

The fixing apertures, slots or knockouts and typically the collar members, generally provide a discontinuity within the corrugated edge surfaces arranged at a common edge thereto.

The tile may comprise a main panel member which is substantially planar; alternatively the member may be substantially non-planar and profiled so as to optimise drainage properties of the tile. The tiles are typically substantially rectangular, or square in shape although it is, of course, envisaged that tiles of other space filling shapes may be used.

Advantageously, the tile is formed from a mineral composition. The composition typically predominantly comprises a mineral powder (such as slate) intimately mixed with a suitable polymer base. The polymer base may, for example, be a thermosetting resin binder (such as polyester), optionally containing a fibre reinforcement. Alternatively, the polymer base may be of a suitable thermoplastics material containing mineral filler.

The tiles are typically prepared by moulding techniques such as compression moulding or injection moulding in a die of required shape.

There is further provided by the present invention a roofing system which comprises a multiplicity of roofing tiles substantially as hereinbefore described. There is still further provided a roofing surface provided with said roofing system.

The roofing system typically further comprises securing means, such as nails or the like, for securing the tiles to a roofing surface.

The present invention will now be further illustrated, by way of example only, by reference to the accompanying diagrams, like parts being denoted by like numerals, wherein:

Figure 1 is a planar view of a tile according to the present invention;

Figure 2 is a sectional view along line A shown in Figure 1; and

Figure 3 is a perspective view of a roofing system according to the present invention when assembled on a roofing surface.

Referring to Figure 1 , there is shown a roof tile generally designated 1 , which comprises offset apertures 2, 3 and a planar panel 4. Aperture 2 is surrounded by collar 5.

Edges 6 of tile 1 are provided with a plurality of rows of teeth 7. Teeth 7 are of a substantially triangular, sawtooth cross-section having a substantially upright back portion 7a and inclined face 7b, the peaks of teeth 7 being spaced apart in a respective longitudinal or lateral direction, as illustrated in Figure 2.

Tile 1 is of a slate composition which predominantly comprises slate powder mixed with a polyester thermosetting resin and fibre reinforcement.

Referring to Figure 2, it can be seen that a second series of rows of teeth 8 are provided along opposed edge 9. Teeth 7 and 8 protrude from tile 1 in opposed directions such that teeth 7 stand proud of face 10 of tile 1, and teeth 8 stand proud of face 11 of tile 1.

In use, when a plurality of tiles 1 are arranged in an overlying arrangement, teeth 7 of a first upper tier of tiles 1 engage teeth 8 of a second lower tier of tiles 1.

Collar 5 is arranged to stand proud of face 10, so as to obviate water leakage through aperture 2 to an underlying surface.

Referring to Figure 3, a plurality of tiles 1 are attached to the battens 12 of a roofing frame generally designated 13. Nails 14 secure tiles 1 to battens 12. Nail 14a passes through the aligned apertures of tiles la and lb so as to secure both tiles to batten 12a. As can be appreciated, this type of arrangement of tiles 1 helps to substantially reduce the number of nails required to secure the assembly of tiles to a roofing frame 13.