GB2186303A

GB2186303A - Roof-surface boundary tile

Info

Publication number: GB2186303A
Application number: GB08703201A
Authority: GB
Inventors: Wilhelm Rottger; Karl-Heinz Hofmann; Manfred Rinklake
Original assignee: Braas GmbH
Current assignee: Braas GmbH
Priority date: 1986-02-12
Filing date: 1987-02-12
Publication date: 1987-08-12
Also published as: DK159832B; DK69687D0; ATA26087A; AT387062B; IT8960453V0; GB8703201D0; DE3604408A1; IT8960453U1; DE3604408C2; DK159832C; GB2186303B; IT8783313A0; IT222559Z2; DK69687A

Abstract

A roof-surface boundary tile which can be laid in conjunction with conventional roofing tiles, especially concrete roofing tiles, has a sloping edge 2 which connects a head-end margin portion 6 to a side-edge portion 4. Grooves 11 in the underside extending parallel to the sloping edge define predetermined breaking lines to simplify trimming. The tile portion including the grooves is made thicker to reinforce the tile in this area. <IMAGE>

Description

SPECIFICATION Roof-surface boundary tile The invention relates to a roof-surface boundary tile. In particular, the invention relates to a roof-surface boundary tile which is intended for limiting the roof surface of a pitched roof adjacent to a ridge.

Specifically described herein is a roof-surface boundary tile which can be laid in conjunction with conventional roofing tiles, especially concrete roof tiles, and which has a sloping edge connecting an upper edge or head-end margin portion to a side-edge portion extending in a direction perpendicular to the head-end margin portion.

Such a roof-surface boundary tile is known from German Offenlegungschrift 3,507,190.

The known roof tile is intended to limit a sloping roof surface adjacent to a ridge or to a valley. At a "ridge" or in a "ridge region", two sloping roof surfaces extending in different directions intercept. The direction of the "ridge line" depends on the slope of the roof and usually extends obliquely relative to the boundary lines which can be obtained by means of conventionally laid roofing tiles mostly having a rectangular base surface. The roofing tiles adjacent to the ridge or valley line are cut obliquely on the building site to make them fit. This operation involves a high outlay and is cost-intensive, since the roofing tiles first have to be placed on the roof battens and the appropriate cutting lines then have to be marked, before roofing-tile material projecting beyond the ridge or valley line can be removed.To avoid this outlay, the known roof-surface boundary tile is made with a sloping edge which extends at an angle of 135 to 150 to each adjoining side edge portion and/or head-end or tail-end margin portion. Simple geometry shows that this configuration can only be satisfied if the sloping edge forms an angle of about 45" with the extension of the side-edge portion.To make it possible for a single design of such a tile to be suitable for different directions of the ridge or valley line which depend on the roof pitch, the distance from the roof battens is varied according to the roof pitch. Specifically, the distance from the roof battens will be calculated from the ratio between the covering width of the roof tiles and a cosine of the roof pitch.Such a measure usually involves too high an outlay under the conditions prevailing on the building site.

In accordance with the present invention there is provided a roof-surface boundary tile for laying in conjunction with conventional roofing tiles, comprising a sloping edge connecting an end margin portion to a side-edge portion extending perpendicularly to said end margin portion, and at least one groove in the underside of the tile extending parallel to and spaced from said sloping edge, the groove defining a predetermined breaking line.

The invention makes it possible for a roofsurface boundary tile to be laid on ordinary roof battens in conjunction with conventional roofing tiles, especially concrete roof tiles, but which tile can nevertheless be matched to widely differing directions of a roof-surface boundary line, which depend on the roof pitch and the like.

Only a few embodiments of a roof-surface boundary tile according to the invention will be needed for matching to the directions of a boundary line which occur in typical roof pitches of a pitched roof.

Preferably, a plurality of grooves each forming a predetermined breaking line are made in the underside of the roof-surface boundary tile within a surface region limited by the sloping edge and by a diagonal, connecting the most distant end points of the side edge opposite the side edge portion and of the end margin opposite the end margin portion. For example, the innermost groove can follow this diagonal, and between this innermost groove and the sloping edge there can be at least three further grooves.

The grooves serve as predetermined breaking points or lines along which the roof-tile material can be broken by means of simple measures. Depending upon the layer thickness of the roof-surface boundary tile, the grooves preferably have a depth of approximately 3 to 8 mm.

The grooves, made at the time when the roof tile is produced, make it possible for the craftsman employed to cover a pitched roof to remove a part of the roof tile not required next to the sloping edge by means of simple tools and measures, for example by means of pliers, in order to trim the roof tile to the necessary dimension in relation to the limiting line, for example a ridge or valley line. It is simple to do this because the grooves provided according to the invention form predetermined breaking points. Thus, there is no need to employ cutting appliances to trim the roof tiles.

In another context, it has already been proposed to provide grooves extending crosswise in the underside of roof tiles, to make it easier to trim such tiles. Because of the multiplicity of intersecting grooves, the breaking resistance of such a roof tile became much lower.

It was therefore impossible to prevent roof tiles from breaking unintentionally in the wrong place, for example during transport or even during trimming.

According to a further feature of the present invention, the roof-surface boundary tiles will preferably have, adjacent to each groove, a thickness exceeding the typical layer thickness of roofing tiles. Preferably, the roof-surface boundary tile can be reinforced in the entire surface region defined in detail above and lo cated between the diagonal and the sloping edge. The depth of the grooves is coordinated with this reinforcement. Because the thickness of the roof tile is made correspondingly larger in the region of the grooves, the danger that a tile will fall to pieces or break unintentionally during trimming is largely prevented.

The invention is explained in more detail below by means of preferred embodiments with reference to the drawings; in the latter: Figure 1 shows a plan view of a roof-surface boundary tile according to the invention for making a ridge connection on the left; Figure 2 shows a plan view of a roof-surface boundary tile according to the invention for making a ridge connection on the right; Figure 3 shows a side view of the tail-end margin portion of a roof-surface boundary tile according to Fig. 1 or Fig. 2; Figure 4 shows a section through the roofsurface boundary tile according to Fig. 1 along the sectional line IV-IV; and Figure 5 shows diagrammatically a portion cut out from the roof covering of a pitched roof with conventional whole and half concrete roof tiles and with roof-surface boundary tiles according to the invention which are adjacent to a ridge.

Pitched roofs typically have a pitch relative to the horizontal of 20 to 60". When two roof surfaces slope at the same angle and are aligned perpendicularly to one another, at the ridge 1 there is a ridge intersection angle which is approximately 43" for a pitch of 20 , approximately 41 for a pitch of 30 , approximately 47" for a pitch of 40 , approximately 32 for a pitch of 50 and approximately 25 for a pitch of 60".

A roof-surface boundary tile 3 which has a sloping edge 2 adjacent to the ridge on the right or left must be matched to the ridge intersection angle. A roof covering typically consists of whole and half roofing tiles, especially concrete roof tiles, which are attached in a uniform laying pattern on roof battens all fastened to the roof substructure at equal distances from one another. Roofing tiles arranged parallel in a row next to one another each overlap the other at a water rebate 8 and a covering rebate 9 in the region of the side edges 4 and 5. The top side 12 of the head-end margin portion 6 of a row of roofing tiles is covered by the underside 10 of the tail-end margin portion 7 of the row of roofing tiles which is the next higher, as seen in the direction of the rectangular base surface.

An advantage of the roof-surface boundary tiles according to the invention is the very fact that they can be laid in conjunction with such conventional roofing tiles, especially concrete roof tiles, and have an appropriate matching profile.

When a roof is covered with such conventional roofing tiles, from one laying row to the next different distances between the particular outermost roof tile and the ridge 1 occur.

Some rough matching can be obtained by using "half" roof tiles. The remaining matching required is done by means of simple trimming, in the region of the sloping edge 2, of the roof-surface boundary tiles 3 according to the invention.

Fig. 1 shows a plan view of a roof-surface boundary tile 3, the sloping edge 2 of which is adjacent to a ridge 1 on the left; Fig. 2 shows a corresponding roof-surface boundary tile 3, but one with its sloping edge 2 adjacent to a ridge 1 on the right. Such a roofsurface boundary tile 3 differs essentially from the conventional roofing tiles, especially concrete roof tiles, in that a corner portion has been removed in the region of the head-end margin 6 at the time of production. A sloping edge 2 now connects the remaining head-end margin portion 6 to a side-edge portion 4; furthermore, additional grooves and, if appropriate, a reinforcement in the region of the grooves are provided on the underside. The rest of the tile 3 is limited by the complete side edge 5 and the complete tail-end margin portion 7.Apart from the differences mentioned, the roof-surface boundary tiles 3 illustrated are typical concrete roof tiles having the profile evident from Fig. 3. As shown, a water rebate 8 is located on the top side in the region of the complete (left-hand) side edge 5, and a covering rebate 9 is located on the underside of the remaining (right-hand) sideedge portion 4. The arch 13 is positioned approximately centrally between these rebates 8 and 9. In the embodiment illustrated, the tail-end margin portion 7 of the boundary tile 3 extends parallel to the remaining head-end margin portion 6; alternatively, the tail-end margin portion 7 could also have another shape different from this.

The sloping edge 2 forms an acute angle a with a straight extension 4' of the particular side-edge portion 4. According to an essential feature of the present invention, this angle a has a value of between 26 and 43 . Within this range there can be various embodiments.

In principle, the angle a of the sloping edge 2 could be matched directly to the ridge intersection angle, but this would require a relatively large number of different roof-surface boundary tiles 3 differing from one another merely in the amount of the angle a. In practice, the roofing tiles or roof-surface boundary tiles adjacent to a ridge 1 are regularly partly covered by ridge capping plates. Slight differences between the direction of the sloping edge 2 and the line of a ridge 1 are acceptable in the region of this covering.

It has been found, within the framework of the invention, that a roof-surface boundary tile 3, the sloping edge 2 of which forms an angle a of approximately 36 to 40 with the extension 4' of the remaining side-edge portion 4, is suitable for most ridge lines resulting from the roof pitches occurring most often in practice. Within the scope of the invention, those roof-surface boundary tiles 3, the sloping edge 2 of which forms an angle of 36 to 40 with the extension 4' of the remaining side-edge portion 4, are preferred. Those roof-surface boundary tiles in which this angle amounts to approximately 38 , are particularly preferred.

According to an alternative embodiment, there can be two different roof-surface boundary tiles 3 which are matched to typical pitches of pitched roofs. In this respect, for pitched roofs with a pitch angle of 20 to 400 there are roof-surface boundary tiles 3, the sloping edge 2 of which forms an angle of 40 to 43 , especially preferably an angle of approximately 41", with the extension 4' of the remaining side-edge portion 4. For pitched roofs with a pitch angle of 40 to 60 , there are then roof-surface boundary tiles 3 the sloping edge 2 of which forms an angle of 30 to 340, especially preferably an angle of approximately 32", with the extension 4' of the remaining side-edge portion 4.

With a range of 2 or 4 different roof-surface boundary tiles 3 for laying on the right or left against a boundary line, such as a ridge, a valley or the like, the invention makes it pos sible to match most "sloping" roof boundaries which occur in practice on pitched roofs.

The direction of the sloping edge 2 arises from the reasoning given above. According to a further important feature of the invention, grooves 11 extending at a distance from and essentially parallel to the sloping edge 2 are made in the underside 10 of each roof-surface boundary tile. These grooves 11 preferably have a trapezoidal cross-section opening outwards, as can be seen clearly in Fig. 4. These grooves 11 in places reduce the roof-tile thickness and form predetermined breaking points.

In the exemplary embodiment illustrated, there are four such grooves 11. In the particular design shown, the distance "e" between the individual grooves 11 and between the sloping edge 2 and the adjacent groove 11 is the same and in practice can be approximately 20 to 30 mm; a distance of approximately 25 mm is especially preferred. Alternatively, however, the distances between adjacent grooves could also be different, for example to increase or decrease starting from the sloping edge 2.

In the particular embodiment shown, the innermost groove 11 extends diagonally between the end point of the complete side edge 5 and the distant end point of the complete tail-end margin portion 7. When the portion of the roof-surface boundary tile 3 located between this innermost groove 11 and the sloping edge 2 is removed, such a tile is reduced to virtually half the base surface of a conventional roof tile, especially a concrete roof tile. In practice, there is no need for a further reduction, because the dimensional compensation in question can be obtained, during the laying of the tiles on the roof, by means of the "half" roofing tiles, especially concrete roof tiles, which are normally available. This measure is shown in Fig. 5, where the whole conventional roofing tiles are designated by 13 and the "half" conventional roofing tiles are designated by 14.As already mentioned, the grooves 11 which, according to the invention, are provided parallel to and at a distance from the sloping edge 2 in the underside of the roof-surface boundary tile, form predetermined breaking points, reducing the roof-tile thickness in places. To guarantee sufficient breaking resistance in spite of these pre-determined breaking points, according to a further important feature of the invention, the roof-tile thickness in the region of each groove 11 is greater than the typical layer thickness of conventional roof tiles, especially concrete roof tiles. Particulars of an exemplary embodiment illustrated in the Figures are explained in detail below with reference to Fig. 4. The roof-surface boundary tiles 3 shown have a length of 420 mm, a width of 330 mm and a typical layer thickness "a" of 11 mm.In the region on both sides of each groove 11, the roof-tile layer thickness is 13 mm, that is to say the roof-surface boundary tile 3 is made approximately 2 mm thicker in the region of each groove 11. Preferably, the entire surface region between the above-mentioned diagonal and the sloping edge 2 is reinforced. The increase in thickness "b" of the reinforced region in relation to the typical layer thickness "a" is preferably approximately 2 to 4 mm and especially preferably approximately 2 mm.

In view of this reinforcement, each groove 11 has, over its entire length, a uniform depth "c" which is preferably approximately 3 to 8 mm and especially preferably approximately 5 mm. In the illustrated embodiment of a roofsurface boundary tile 3, in the region of each groove 11 a uniform predetermined breaking thickness "d" of approximately 8 mm remains between the groove bottom and the roof-tile top side 12. This remaining layer thickness "d" of approximately 8 mm gives the roofsurface boundary tile 3 sufficient breaking resistance.

Fig. 5 shows diagrammatically a portion cut out from the roof covering of a pitched roof.

Conventional concrete roof tiles 13 are attached in parallel laying rows on roof battens (not shown). If required, "half" concrete roof tiles 14 are also provided in individual laying rows. The roof surface requires a sloping roof-surface boundary adjacent to a boundary line 1. This boundary line 1 can be a ridge or a valley leading to an adjacent sloping roof surface or a boundary with another roof projection or the like. Adjacent to this boundary line 1, each laying row ends in a roof-surface boundary tile 3 according to the invention, the sloping edge 2 of which extends essentially parallel to the boundary line 1. As indicated diagrammatically by the number of grooves 11 represented by broken lines, certain individual roof-surface boundary tiles 3 do not have to be trimmed, whereas other roof-surface boundary tiles 3 have been trimmed. This trimming is carried out by removing a sufficiently wide portion between the sloping edge 2 and a suitable groove 11. Because these grooves 11 are designed as predetermined breaking points, trimming can usually be carried out by the craftsman simply by means of suitable pliers.

Claims

1. A roof-surface boundary tile for laying in conjunction with conventional roofing tiles, comprising a sloping edge connecting an end margin portion to a side-edge portion extending perpendicularly to said end margin portion, and at least one groove in the underside of the tile extending parallel to and spaced from said sloping edge, the groove defining a predetermined breaking line.

2. A tile according to claim 1, wherein a plurality of grooves are provided in the underside of the tile within a surface region limited by the sloping edge and a diagonal interconnecting the most distant end points of the side edge opposite said side edge portion and the end margin opposite the end margin portion.

3. A tile according to claim 2, wherein the innermost groove extends along said diagonal, and there are at least three further grooves between said innermost groove and the sloping edge.

4. A tile according to any one of claims 1 to 3, wherein the spacing between the sloping edge and the adjacent groove and/or the spacing between adjacent grooves is approximately 20 to 30 mm.

5. A tile according to any one of claims 1 to 4, wherein the tile has a layer thickness typical for conventional roofing tiles, and adjacent the or each groove the tile has an increased thickness greater than for typical roofing tiles.

6. A tile according to claim 5, wherein the entire region between the sloping edge and the diagonal connecting the most distant end points of the side edge and end margin opposite the side edge and end margin portions, respectively, is reinforced.

7. A tile according to claim 5 or 6, wherein the thickness increase is approximately 2 to 4 mm.

8. A tile according to any one of claims 1 to 7, wherein the depth of each groove is approximately 3 to 8 mm.

9. A tile according to any one of claims 1 to 8, wherein the sloping edge forms an angle of 26 to 43" with an extension of said sideedge portion.

10. A tile according to any one of claims 1 to 9, wherein the sloping edge forms an angle of 36 to 40 , with an extension of said side-edge portion.

11. A tile according to claim 10, wherein said angle is substantially 38".

12. A tile according to any one of claims 1 to 9, wherein the sloping edge forms an angle of 30 to 34 with an extension of the side-edge portion.

13. A tile according to claim 12, wherein said angle is substantially 32".

14. A tile according to any one of claims 1 to 9, wherein the sloping edge forms an angle of 40 to 43 , with an extension of said side-edge portion.

15. A tile according to claim 14, wherein said angle is substantially 41 .

16. A method of limiting the roof surface of a pitched roof adjacent to a ridge by use of a roof-surface boundary tile according to any one of the preceding claims.

17. A method according to claim 16, wherein the pitched roof has an angle of inclination of 20 to 40 , and said tile is as defined in claim 12 or 13.

18. A method according to claim 16, wherein the pitched roof has an angle of inclination of 40 to 60 and said tile is as defined in claim 14 or 15.

19. A roof-surface boundary tile substantially as herein described with reference to the accompanying drawings.