GB2312689A

GB2312689A - Roof tiles

Info

Publication number: GB2312689A
Application number: GB9609308A
Authority: GB
Inventors: Gerald Emerton
Original assignee: MARLEY BUILDING MATERIALS Ltd
Current assignee: MARLEY BUILDING MATERIALS Ltd
Priority date: 1996-05-03
Filing date: 1996-05-03
Publication date: 1997-11-05
Anticipated expiration: 2016-05-03
Also published as: GB2312689B; GB9609308D0

Abstract

A profiled roof tile 1 is provided with a retaining nib (19,20) at the head and tail ends (2,3) for hooking over the tile battens. In this way the tiles can be made reversible to facilitate tiling from either the left or the right directions. The ends are arranged to allow stacking of the tiles, and are shaped to sit inside the trough of the tile above.

Description

Roof Tulles The present specification relates to improvements in roof tiles.

Interlocking roof tiles have been known for many years. Such tiles have interlocking side-lock portions provided on opposing surfaces of the tile. These sidelock portions usually extend the full length along the side edges of the tile between the head and tail ends of the tile, and generally comprise a channel and a rib arrangement which can interengage and lock with a similarly profiled but oppositely, i.e. upwardly as opposed to downwardly, facing channel and rib side-lock portion of an adjacent tile. Thus, one side of the tile has an underlock portion and the other side has an overlock portion and in use, the overlock portion of one tile overlies and engages the underlock portion of an adjacent tile.

Over the years, the practice has been established of providing the underlock portion on the left-hand side of the tile and the overlock portion on the right-hand side. This practice has led to a particular pattern of placement of tiles during tiling, namely commencing from the right-hand side of the roof and working across to the left, repeating the process for successive courses of tiles.

The "left-hand side" and "right-hand side" of the tile as used herein are those sides when viewing the tile as it would be positioned on a roof, ie. viewing its upper surface, with the head end of the tile at the top and the tail end at the bottom.

Tiles having interlocking side-lock portions as described above often are provided with a retaining nib on the underside of the roof tile to retain it in position on the roof structure. The retaining nib generally projects from the underside close to the head end of the tile and is intended to hook over a tile batten in use to locate the tile on the roof structure.

The tail end of the tile may also incorporate clip troughs or nailing points for securing the lower end of the tile to the roof structure to prevent it from being lifted by gusts of wind.

A problem with tiling from right to left or left to right is that roof surfaces are seldom free of projecting surfaces such as chimneys or abutments, and in many cases, for particular regions of the roof at least, it may be easier to tile in the opposite direction, ie. from left to right.

A first invention disclosed herein seeks to alleviate the above problem by providing a roof tile comprising retaining nibs for hooking over a tile batten provided on the underside of the tile adjacent both the head and tail ends.

By providing at least two retaining nibs, one at the head end and one at the tail end of the tile, the tile can be made reversible. That is to say, the tile may be used in two different orientations; using the retaining nib at the head end of the tile to hook over the tile batten in a first configuration or using the retaining nib at the tail end of the tile, with the tile rotated through 1800, to hook over the tile batten in a second configuration.

With such a tile, the economic savings are obvious over producing two versions of a given tile, and in addition the tiler has the choice of tiling from right to left or from left to right as he pleases, with perhaps even a combination of the two being used for successive courses of tiles. This provides much greater flexibility for working around features projecting from the roof plane without having to resort to lifting and cutting the tiles to obtain the desired fit.

A further advantage in providing the flexibility to lay the tiles in either a left to right or right to left orientation is that the interlock portions can be positioned on either the left side of an undulation or on the right side. Thus for any roof elevation the tiling can be arranged so as to hide the joint behind the array of undulations in the line of sight from the most likely viewpoint of an observer. Hence for any portion of the roof which is likely to be viewed side on, the most aesthetically pleasing orientation of the tiles can be presented to the observer.

Preferably the tile is symmetrical about a line mid-way between the head and tail ends of the tile, as this allows the tile to be reversed without changing its outward appearance. A symmetrical shape also makes the tile better balanced and easier to handle by the tiler.

The invention may be applied to substantially planar tiles, although in its more preferred embodiments it applies to tiles which are profiled, for example, pan tiles in which an undulation or corrugation runs along the length of the tile between the head and tail ends.

Such a tile has a cross-sectional profile with at least one trough and one ridge. Depending on the size of the tile, it may include more than one undulation. The undulation may be a smooth curve, for example, U-shaped, or it may be angular, for example, V-shaped, which is preferred.

Preferably the retaining nibs are formed by a recess in the tile which extends substantially but not entirely the full length between the head and tail ends, across the trough of an undulation on the underside of the tile. The material which projects from either side of the recess then forms the retaining nibs. Such an arrangement has the advantage that the retaining nib does not extend beyond the profile of the tile, which means that at its tail end, the underside of the tile can engage the upper surface of an underlying tile of a lower course without its tail edge standing proud therefrom.

The underside of the tile can therefore have shape which is complementary to the upper surface, whilst still including the provision of retaining nibs, the retaining nibs of the profiled tile extending into and filling the trough of a lower tile. The complementary upper and lower surfaces also allow the tiles to be easily stacked upon one another before they are used by the tiler, or preferably side by side on their edges which are stronger to avoid breakage. The provision of a retaining nib at the tail end of the tile also provides for a close fit to the facia board or tilt at the eave of tiling.

The retaining nibs may be provided by a single recess or cut-out extending substantially the length of the tile or may be provided by separate recesses or cutouts, for example, slots formed at both ends of the tile. If the tile includes more than one undulation then recesses must be provided in the floors of all the undulations to enable the tile to lie flat against a tile batten. The recess or recesses are preferably arranged symmetrically in the tile so that the weight distribution is the same irrespective of the orientation of the tile.

Preferably the floor of the recess is flat so as to provide a flat surface for engagement with a batten in order to transfer the load of the tile efficiently to the tile batten, although the recess may have a scooped configuration or plurality of further recesses to reduce weight and save material. In addition small projections may be provided in the floor of the recess to lift the tile undersurface away from the batten, thereby reducing the potential for the development of humid conditions on the batten surface and hence the likelihood of fungal or bacterial decay.

Formation of a retaining nib in a profiled tile in the above described manner provides advantages, such as an improved edge appearance, regardless of whether it is incorporated into a design of a reversible tile.

Thus according to a further invention disclosed herein, there is provided a profiled roof tile having a ridge and a trough extending along its length between the head and tail ends of the tile, the tile including a retaining nib on its undersurface adjacent the head end of the tile for hooking over a tile batten, wherein the retaining nib is formed by providing a recess on the underside of the tile which extends across the base of the trought.

The provision of a recess at the tail end of the tile to form a retaining nib is also beneficial since it creates an anticapillary device by providing a gap between the two complementary surfaces of overlapping tiles in successive courses. This is a particularly important feature for a profiled tile since rain water will drain to the troughs of the undulations and therefore provision of such an anticapillary device in the troughs can prevent water from being drawn up into the roof structure.

Thus according to another invention disclosed herein, there is provided a profiled roof tile having a ridge and a trough extending along its length between the head and tail ends of the tile, wherein a recess is provided in the underside adjacent the tail edge of the tile, the recess extending across the base of the trough to form an anticapillary device.

Preferably the tile has opposite interlocking sidelock portions provided along the left and right sides of the tile between the head and tail ends. Preferably these comprise underlock and overlock portions having complementary channel surfaces, with the overlock on the right-hand side and the underlock on the left since this fits in with the established pattern of tiling discussed previously, lending naturally to the single action of laying the tile into position without the need to turn the tile by hand in the process of laying. In such locks, the outer edge of the channel of a side-lock portion of a first tile forms a rib which engages and locks with a channel of a side-lock portion of an adjoining tile.

If the tile is profiled, then the side-lock portions are preferably arranged so that the junction between the over and the underlock forms part of a sloping surface of an undulation. Preferably the junction is formed above the half-way point of the slope and most preferably substantially at the top of the undulation, ie. close to the ridge. In this way, less water will be channelled into the side-lock.

In addition, preferably it is the overlock portion which extends from the ridge with the underlock portion extending from the trough, as this too can reduce the penetration of water. This is because the junction surface of the interlocking side-lock portions angles upwardly with the rib of the underlock providing a barrier with a high kerb height to the water. It may also be beneficial to slightly angle the junction of the interlocking side-lock portions towards the trough, from the head end to the tail end of the tile. In this way, water in the joint is directed back onto the surface of the tile below where it can flow away via the trough as normal.

These side-lock features provide advantages independently of the above-mentioned inventions. Thus, according to yet another invention described herein, there is provided a profiled roof tile having interlocking side-lock portions comprising over and underlock portions arranged along opposing edges of the tile between the head and tail ends, wherein the interlocking side-lock portions are arranged so that the junction with a corresponding portion of an adjoining tile is formed on a slope between a ridge and a trough with the overlock portion extending down the slope from the ridge.

With such a tile the trailing edge of the tile, in this case the underlock is raised from the batten, making it comfortable for the tiler and leaving ample room for the hand to be withdrawn following laying the tile in position.

If nailing points are provided to secure the tile to the tile battens, preferably these are provided in the form of blind holes located part way up the slope between a trough and a ridge to minimise water penetration as much as possible. The position of the nailing points on the slope are preferably chosen so that the nail passes through the tile and into the tile batten just to the side of the tile batten recess in the underside of the tile. Recesses or clip troughs may also, or alternately, be provided at both ends of the underlock (in the case of the reversible tile) for the application of tile clips.

The underside of tile may also include a central cut-out to reduce the weight of the tile and to minimise the amount of material required for the production of the tile. This produces a good weight distribution which makes the tile less prone to being disturbed by gusts of wind, and if symmetrical, will produce a tile that is easy to handle by the tiler. The central cutout may open into the recess or recesses which form the retaining nibs.

The tile may be made using the conventional techniques of roller slipper extrusion. In such a process, the underside of the tile is shaped to the desired profile by casting the material in a pallet which moulds the underside surface of the tile, whilst the upper surface of the tile is scraped to the desired profile when the material is semi-hard by the action of a roller and slipper. The undersides of the above tiles require only simple and uncomplicated pallet designs.

The preferred material for the tile is concrete, preferably including a pigment addition to give the tile a desired colouration. However, other materials such as fired clay, polymer or metal may be appropriate in certain situations.

Some preferred embodiments will now be described by way of example only and with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of an array of profiled angular tiles on a series of tile battens; Figure 2 shows a perspective view of the underside of a preferred tile; Figure 3 shows a side elevation of the tile shown in Figure 2 when viewed the correct way up; Figure 4 shows a side elevation of another preferred tile having a plurality of undulations; and Figure 5 shows a perspective view of the tile of Figures 2 and 3.

An array of nine interlocking tiles is shown in Figure 1. Figure 2 shows one of these tiles 1 in greater detail when viewed from the underside. The tiles 1 are substantially rectangular, each with a head end 2, a tail end 3, a left-hand side 4 and a right-hand side 5 (left and right sides of the tile are reversed in Figure 2 since the tile is upside down). The tiles 1 are symmetrical about a plane mid-way between the head and tail ends 2,3, making the tiles 1 reversible, ie.

they can be laid by tiling from right to left or from left to right as desired.

Along the right-hand side 5 of the tile 1 there is provided one half of a side-lock, preferably an overlock 6, and along the left-hand side 4 there is provided the other corresponding half of the side-lock, the underlock 7. These side-lock portions 6,7 have complementary surfaces such that an overlock 6 of one tile 1 may hook over and engage with an underlock 7 of an adjacent tile 1 to lock the two tiles together side by side. As shown more clearly in Figure 3 and Figure 5, these side-lock portions 6,7 consist of two channels 8,9 which interlock with the corresponding channels 8,9 of adjacent tiles 1.

They interlock because the outer edge of the overlock channel 8 forms a rib 10 which projects downwardly in use and fits within the underlock channel 9, and the outer edge of the under lock channel 9 does likewise forming rib 11 which projects upwardly in use and fits within the overlock channel 8.

As shown in Figure 1, the tiles lie on the roof structure with their head ends 2 supported by a tile batten 27 and their tail ends 3 resting on an underlying tile 1 of a lower course of tiles, completely filing the troughs 26 of those tiles. If necessary, the tail ends 3 of the tiles 1 can be secured to the tile battens 27 with nails inserted through nail holes (not shown).

Ideally, the holes are blind, ie they do not extend all the way through the tile, as this reduces the risk of water entering the roof structure. Alternatively, clip troughs (also not shown) may be provided in the underlock to receive clips for clipping the tail end 3 of the tiles 1 to the tile battens 27.

As shown in the Figures 1 to 3, the tile is profiled and includes sloping sides 12,13 to create a zig-zag structure defining an undulation 14 which extends along the length of the tile 1 between the head and tail ends 2,3. Preferably the sloping sides 12,13 incline at an angle of less than 20 . As well as being more aesthetically pleasing, the flatter tile (which preferably has flat slopes as shown) makes marking and cutting easier. It also requires less mortar for fitting in along the verge. The underside 15 of the tile 1 is complementary with the upper surface 16 so that successive courses of tiles may be laid without the tail edge regions of the tiles 1 standing proud. The tiles do not necessarily have to be laid with the interlocking side-lock portions 6,7 aligned as shown in Figure 1, but may be staggered like brickwork.

In the underside 15 of the tile 1 shown in Figure 2, two recesses 17,18 are provided adjacent the head and tail ends 2,3 respectively. The recesses 17,18 extend across the floor or trough of the undulation 14 on the underside of the tile 1 to define two retaining nibs 19,20, which consist of the remaining material that forms the edges of the head and tail ends 2,3. The retaining nibs 19,20 hook over a tile batten 27 to retain the tile 1 on the roof structure. The orientation of the tile 1 and the particular retaining nib 19,20 used for this purpose will depend on whether the tiler is tiling from right to left, as is conventional, or from left to right. The floor 21 of the illustrated recesses 17,18 is planar so that the tile 1 can rest flat on a tile batten 27, thereby spreading the load most efficiently, in order to witstand being trodden on, for example, by the tiler.

Alternatively, small rib projections (not shown) can be added to provide ventilation between the tile 1 and the tile batten 27. A cut-out 22 is provided in the centre of the underside of the tile 1 to reduce weight. The recesses 17,18 and cut-out 22 are arranged symmetrically to produce a tile 1 with a balanced weight distribution, which is easier for the tiler to use and carry.

As can be seen from Figure 3, because the tile batten 27 is located in the recess 18 in the underside 15 of the tile 1, a retaining nib 19,20 is formed without requiring the provision of a separate projection from the undersurface. This means that the tail end edge 3 of the tile 1 rests flush against the upper surface 16 of a lower tile 1, without the retaining nib 20 forcing the edge to stand proud. Thus, the observer viewing the roof structure sees the tiles 1 lying neatly upon one another with no large spaces between the tail end 3 of an upper tile 1 and the trought 26 of a lower tile 1.

The retaining nib 20 and recess 18 of the tail end 3 also double as an anticapillary device, the recess 18 providing a break to stop capillary action along the contacting surface of two overlapping tiles. This anticapillary device is located in the trough 26 of an undulation 14 where water is likely to collect.

Another feature shown in Figure 3 is the position of the side-lock portions 6,7 with respect to the sloping sides 12,13 of the corrugation. Preferably the overlock 6 of a first tile 1 joins with an underlock 7 of an adjacent tile 1 to form a sloping surface 23,24 which matches sloping side 12, with the overlock 6 extending from above the junction from the ridge 25, and the underlock 7 extending from below from the trough 26.

In this way, the rib 11 of the underlock 7 provides a high barrier to entry for rain water. As can be seen from Figure 3, the junction between the overlock 6 and corresponding underlock 7 of an adjoining tile will be formed above the half-way point of the slope 23,24.

Figure 4 shows another preferred embodiment of the tile 1 which includes more than one undulation 14. The underside 15 of the tile 1 has substantially the same features as the tile 1 shown in Figure 2, only the recesses 17,18 and cut-out 22 are repeated for each undulation 14.

Thus, at least in the illustrated embodiments there has been described a novel reversible roof tile which offers the tiler greater flexibility, has a good weight distribution and is aesthetically pleasing.

Claims

1. A roof tile having retaining nibs for hooking over a tile batten wherein the retaining nibs are provided on the underside of the tile adjacent both the head and tail ends.

2. A tile as claimed in claim 1, wherein the tile is symmetrical about a line mid-way between the head and tail ends of the tile.

3. A tile as claimed in claim 1 or 2, wherein the tile is profiled such that it has at least one undulation.

4. A tile as claimed in claim 3, wherein the retaining nibs are formed by a recess in the tile which extends substantially but not entirely the full length between the head and tail ends, across the trough of an undulation on the underside of the tile.

5. A tile as claimed in claim 3, wherein the retaining nibs are formed by recesses which extend across the trough of an undulation on the underside of the tile at the head and tail ends.

6. A tile as claimed in claim 4 or 5, wherein the floor of the recess or recesses is/are flat for engagement with a tile batten.

7. A tile as claimed in any preceding claim, wherein the underside of the tile is shaped to be complementary to the upper surface of the tile so as to facilitate stacking of the tiles.

8. A profiled roof tile having a ridge and a trough extending along its length between the head and tail ends of the tile, the tile including a retaining nib on its undersurface adjacent the head end of the tile for hooking over a tile batten, wherein the retaining nib is formed by providing a recess on the underside of the tile which extends across the base of the trough.

9. A profiled roof tile having a ridge and a trough extending along its length between the head and tail ends of the tile, wherein a recess is provided in the underside adjacent the tail edge of the tile, the recess extending across the base of the trough to form an anticapillary device.

10. A tile as claimed in any preceding claim, wherein an under lock portion and an over lock portion having complementary surfaces are provided along opposite edges of the tile extending between the head and tail ends.

11. A profiled roof tile having interlocking side-lock portions comprising over and underlock portions arranged along opposing edges of the tile between the head and tail ends, wherein the interlocking side-lock portions are arranged so that the junction with a corresponding portion of an adjoining tile is formed on a slope between a ridge and a trough of and undulation with the overlock portion extending down the slope from the ridge.

12. A tile as claimed in any preceding claim, wherein nailing points are provided to secure the tile to a tile batten in the form of blind holes.

13. A tile as claimed in any preceding claim, further including a central cut-out on the underside of the tile.

14. A roof tile substantially as hereinbefore described with reference to Figure 1, Figures 2, 3 and 5 or to Figure 4.