A Roof Panel

Technical Field

This invention relates to a roof panel suitable for sheathing, particularly but not restricted to, at least part of an open roof of a house or building.

Background of the Invention

Conventional roofing systems involve utilising tiles, slates or shingles to form an external covering for the roof of a house or building. Each tile, slate or shingle typically overlaps with a few other tiles, slates or shingles in order to provide waterproofing.

Placement of tiles, slates or shingles require a rigid support structure or base which typically includes rafters located at the upper section of the frame of the house or building. Before the tiles, slates or shingles may be placed, battens have to be provided and mounted onto the rafters, followed by an overlay of sarking. The tiles, slates or shingles are then installed individually by installers who routinely carry them around the roof walking on the rafters and battens forming a typically slanting slope. In order to effect waterproofing, installers often have to walk on the thin rafters and battens repeatedly for the fitting of the battens and sarking, and then installation of the numerous pieces of tile, slate or shingle.

The above conventional way of laying tiles, slates or shingles has the shortcomings of:

1. requiring a large quantity of tiles, slates or shingles which typically overlap with each other over a large area to provide waterproofing;

2. posing work safety issues with installers having to walk on thin rafters and battens carrying a heavy stack of tiles, slates or shingles, particularly in windy or slippery weather conditions;

3. requiring the installation of battens and sarking, which increases material and labour costs; and

4. adding substantial weight to the roof structure.

Previous attempts have been made to use small independent panels of pressed or moulded metals to cover an open roof. These panels however are somewhat flimsy and have to be used in combination with battens and sarking to provide waterproofing.

It is therefore an object of the present invention to provide a roofing system and a method of implementing such a system which may overcome or ameliorate the above shortcomings, or which will at least provide a useful alternative.

Disclosure of the Invention

According to one aspect of the present invention, there is provided a roof panel including:

a face surface resembling a plurality of roof elements;

support means for the face surface, the support means being adapted to be fixed to a roof rafter; and

means for interlocking the roof panel with an adjacent roof panel;

wherein the roof panel, by itself or when interlocked with one or more other roof panels, is capable of providing a weight bearing roof surface without use of battens.

In a second aspect, the invention provides a roof constructed from a plurality of the roof panels of the invention, together with a plurality of roof rafters.

In a third aspect, the invention provides, in a method of constructing a roof, the steps of:

(a) providing first and second roof rafters, the first rafter being generally parallel to and spaced from the second rafter to form a rafter gap;

(b) affixing a roof panel of the invention to the first and second roof rafters, the roof panel having a span greater than the gap.

In the roof panel of the invention, the face surface resembles at least two, and preferably four or five, roof elements. A roof element is this regard is preferably a tile, slate or shingle. The face surface is preferably a slice of tile, slate or shingle, of less thickness than a normal tile, slate or shingle. It will be appreciated that this can represent a saving in both cost and weight compared to a conventional tile, slate or shingle.

The support means may take any suitable form. It is preferred that the support means is a pre-folded pressed aluminium panel, presenting a surface, preferably flat, to which the face surface may be adhered or otherwise bonded.

In an especially preferred embodiment, the support means includes an insulating material, more preferably high density foam. It will be appreciated by one skilled in the art that in this embodiment insulation provided by the roof panel to the building beneath may be of a high degree and can eliminate the need for sarking or other insulation.

The means for interlocking the roof panel with an adjacent roof panel may take any suitable form. Preferably the interlocking means provides for overlap between one panel and the adjacent panel in at least one direction. Overlap may be provided for in two directions, so that one roof panel can overlap an adjacent "downhill" panel and at the same time a panel in the same row.

In one preferred embodiment, the interlocking means includes a rebate and a tongue, adapted to mate with a tongue and a rebate (respectively) on an adjacent panel.

In the roof system of the present invention, conveniently, the series of roof panels are arranged in rows. It is preferred that rows are staggered, so that a join between adjacent roof panels in one row is not located directly in line with a join between roof panels in an adjacent row. When a panel is not located in a top or bottom row, it may interlock with the adjacent panels located in the rows both above and below.

In a preferred embodiment, the roof panel of the invention is not of constant cross section throughout. It is preferred that one end is thicker than the other, so that when a roof panel is interlocked with the adjacent roof panel, the thinner end of one roof panel is located next to the thicker end of the adjacent roof panel. This configuration can better provide for overlap of one roof panel with the other. In this regard it is preferred that the overlap is provided by an extension of the face surface, but other configurations are possible.

It is preferred that each panel is secured onto one or more rafters by one or more fastening means, such as screws.

The or each panel, particularly that positioned at the top or bottom of a slanting roof, may be customised to suit different purposes. For instance, the or each panel may be trimmed to fit a ridge and/or hip of the roof so as to allow installation of weatherproof flashings. Also, the panel may be trimmed to permit fitting of flashings to lap over a gutter or an edge, or to cover a valley, or to protect an angle or break in a wall of the frame, or to protect a position where the roof comes into contact with a chimney.

In relation to the method of the invention, it is preferred that in step (b) the first roof panel is affixed to the first rafter at the end of the rafter which will be at the bottom of the finished roof. The roof panel preferably overhangs any gutter provided for water runoff. The panel is preferably affixed using screws.

For ease of handling, it is preferred that the roof panel of the invention has a span greater than the rafter gap provided in most building situations. In this

circumstance, each roof panel may be securely held in place by at least two rafters. Also, each roof panel may be positioned such that it laterally abuts at least one adjacent panel in the same row. It is preferred that a bridging roof element is provided between one roof panel and an adjacent roof panel in the row, to assist in water runoff. The joining of adjacent roof panels may include interlocking of those panels.

The method may include a further step of trimming the panel when positioned at the top and/or bottom of the rafter.

Brief Description of the Drawings

The invention may be better understood from the following non-limiting description of preferred embodiments, in which:

Figure 1 is a perspective view of a roof during construction from roof panels in accordance with one embodiment of the invention;

Figure 2a is a plan view of one of the roof panels of Figure 1;

Figure 2b is a side elevation of the roof panel of Figure 2a;

Figure 3 is an exploded cross sectional view of the roof panel of Figure 2;

Figure 4 is an assembled cross sectional view of the roof panel of Figure 2;

Figure 5 is a side elevation of the roof panels of Figure 1, before interlocking;

Figure 6 is a side elevation of the roof panels of Figure 1, after interlocking;

Figure 7 is a schematic plan view of the roof panels of Figure 1;

Figure 8a is a side elevation of another embodiment of the roof panel of the invention;

Figure 8b is a perspective view of the roof panel of Figure 8a in use;

Figure 9 is a side view of the roof panels of Figure 1, during assembly; and

Figure 10 is a side view of the roof panels of Figure 1, after assembly.

Detailed Description of the Drawings

Possible and preferred features of the present invention will now be described with particular reference to the accompanying drawings. However, it is to be understood that the features illustrated in and described with reference to the drawings are not to be construed as limiting on the scope of the invention.

In a general sense, the present invention is for sheathing an open roof 1 supported by a frame of a house or building (not shown).

Referring to Figure 1, a first roof panel 10 includes a face surface 12, a support means 14 for the face surface 12, and a means 16 for interlocking the roof panel 10 with an adjacent, identical roof panel 18. The face surface 12 resembles a plurality of slate roof elements 20. The support means 14 is fixed to roof rafters 22 by screws 21.

Each of panels 10 and 18 includes high density insulation foam 28.

The roof panel 10, by itself or when interlocked with adjacent roof panel 18, is capable of providing a weight bearing roof surface without use of battens. It may be seen from Figure 1 that a roof 24 is constructed from the roof panels 10 & 18, together with the roof rafters 22. Roof rafters 22 are separated by gap 66.

Turning to Figures 2a and b, in this embodiment, the face surface 12 resembles five juxtaposed roof elements 20a to 2Oe. Each roof element 20 may be a tile in a slate, tile or shingle, but this embodiment resembles a slate. The face surface 12 is a slice of slate of less thickness than a normal slate. It will be appreciated that this can represent a saving in both cost and weight compared to a conventional slate.

Support means 14 is shown projecting from panel 10 at the base of panel 10. Figures 2a and 2b also show how slate element 2Oe projects from support means 14. This is to facilitate overlap with an adjoining panel. Support means 14 also projects from panel 10 so that slate element 2Oe is recessed. This allows an 5 adjoining panel to overlap panel 10, with slate element 20a on one panel abutting slate element 2Oe on an adjoining panel.

Referring now to Figures 3 and 4, in this embodiment, the support means 14 is a pre-folded pressed aluminium panel 24, presenting a flat surface 26 to which the face surface 12 is adhered or otherwise bonded. o The support means 14 includes an insulating material 28 which is a high density foam. It should be noted that the insulation provided by the roof panel 10 to the building beneath is of a high degree and hence eliminates the need for sarking or other insulation.

Referring to Figure 5, the means 16 provides for overlap between the panel 10 and5 the adjacent panel 18 in the direction as indicated by arrow 30. It is contemplated that overlap may be provided for in two directions if required, so that the roof panel 18 can overlap the adjacent "downhill" panel 10 and at the same time a panel in the same row (not shown). The overlap with the panel in the same row will be described further in detail below. The panel 18 has an extension 56 to overlap theo adjacent downhill panel 10.

In one embodiment, the interlocking means 16 includes a rebate 32 and a tongue 34. As best shown in Figure 6, the rebate 32 and tongue 34 of the roof panel 18 are adapted to mate with another tongue 36 and another rebate 38, respectively, on the adjacent panel 10. Referring to Figures 3 to 6, the rebates 32 & 38 and tongues 345 & 36 are rectangular in shape.

Referring to Figures 7a and b, in another embodiment, the roof panel 10' includes a tongue 34' which is in the shape of a wedge at one end and a rebate 40' which is

shaped complementarity to conform to the shape of the wedge at an opposing end. It is contemplated that the tongues and rebates of each panel may take other forms or shapes adapted to facilitate interlocking with the one or more adjacent panels. The roof panel 10' has an extension 56' similar to the extension 56 of panel 18 (see Figure 5).

Referring to Figures 1, 6 and 7 conveniently, the series of roof panels 10 & 18 are arranged in rows 42, 44 & 46. The rows 42, 44 & 46 are staggered, so that a join 47 between adjacent roof panels in one row is not located directly in line with another join 49 between roof panels in an adjacent row. Also, as shown in Figure 6, when a panel such as panel 18 is not located in a top or bottom row, it may interlock with the adjacent panels 10 & 48 located in the rows 42 & 46 both above and below.

In this embodiment, the roof panels 10 and 18 (and all of the other panels) are not of constant cross section throughout. It can be observed from Figure 6 for panel 18 that one panel 18 end 50 is thicker than the other end 52. As such, when the roof panel 18 is interlocked with, for example, adjacent roof panel 48, the thinner end 52 of the roof panel 18 is located next to the thicker end 54 of the adjacent roof panel 48. This configuration can better provide for overlap of one roof panel with the other. In this regard, the overlap is provided by an extension 56 or 56' (see Figures 5 and 8a and 8b) of the face surface 12 or 12', but other configurations are possible.

As can be seen in Figure 6, each panel 10 & 18 is secured onto at least one rafter 22 by a fastening means such as a screw 58 in the present embodiment.

It is contemplated that the or each panel 10, 18 & 48, particularly that positioned at the top or bottom of the slanting roof 1 (see Figure 1), may be customised to suit different purposes. For instance, the panel 48 may be trimmed to fit a ridge and/or hip (not shown) of the roof 1 so as to allow installation of weatherproof flashings

(not shown). Also, the panel 10, for example, may be trimmed to permit fitting of flashings to lap over a gutter or an edge, or to cover a valley, or to protect an angle or break in a wall of the frame of the house of building, or to protect a position where the roof 1 comes into contact with a chimney.

5 As shown in Figure 9, for ease of handling, the roof panel 10 has a span greater than the rafter gap 66 indicated by A-A. In this circumstance, the roof panel 10 is securely held in place by two rafters 22. The roof panel 10 is positioned such that it laterally abuts an adjacent panel 60 in the same row. A projection 62 of roof element 2Oe is provided between the roof panel 10 and the adjacent roof panel 60 io in the row, to assist in water runoff. As such, as shown in Figure 10, the roof element 2Oe is supported by and overlaps both roof panels 10 and 60 thereby preventing leakage of rain through a gap 64 between roof panels 10 and 60. It is anticipated that the joining of adjacent roof panels 10 & 60 may include interlocking of those panels.

15 The general steps involved in constructing a roof using the roof panel of the present invention will now be described. It should be appreciated that this is only for exemplary purposes and the steps may be carried out in any order deemed fit by a user such as a builder. The roof rafters 22 are provided in the open roof. The rafters 22 are generally parallel to and spaced from one another to form a rafter gap

20 66 (refer to Figure 1). The first roof panel, for example 10, is affixed to two adjacent roof rafters 22. Panel 10 has a span greater than the rafter gap 66. Logically, the first roof panel 10 to be installed is affixed to the first rafter at the end of the rafter which will be at the bottom of the finished roof. The roof panel 10 overhangs any gutter provided for water runoff. The roof panel 10 is then affixed

25 using screws 58. For those roof panels that are positioned at the top and/or bottom of the rafters 22, a further step of trimming their edges may be carried out for aesthetic purposes.

A second roof panel, for example 60, is then placed on the open roof and abutted laterally to the first roof panel 10. The roof element 2Oe is held by both the first and second roof panels 10 & 60 so as to prevent water leakage through the gap 64. The second roof panel 60 is affixed to another pair of rafters.

This step is carried out repeatedly until the length of the bottom of the open roof 1 is covered. A third "uphill" roof panel, for example 18, is placed on the now partially open roof to start another row. The interlocking means 16 described above are used to lock the roof panels in place with respect to each other such that the extensions 56 can function effectively to prevent leakage in rainy or stormy weather.

Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. AU such variations and modifications are to be considered within the scope and spirit of the present invention the nature of which is to be determined from the foregoing description.

Industrial Applicability

The present invention has industrial applicability in that at least in some embodiments it provides a roof panel which is capable of offering at least the following advantages:

(i) no sarking or battens are required;

(ii) no separate thermal insulation is required;

(iii) labour costs are reduced due to the omission of sarking, battens and thermal insulation;

(iv) there is a substantial reduction in the quantity of tiles, slates and shingles required;

(v) safe and easy installation is enabled; and

(vi) superior sound and noise retention are provided.