GB2211869A - Tile or slate with plural drainage grooves - Google Patents

Abstract

A roofing member, in the form of a slate, artificial slate, tile or like generally flat, rectangular member having at least one ventilation drainage recess 27 on the normally lower surface and extending from a normally upper edge or region of the member towards the normally lower edge or region of the member where said ventilation drainage recess runs into a groove or recess 33 extending across the normally lower edge region of said member and acting as capillary action limiting or prevention means which also facilitates ventilation. <IMAGE>

Description

ROOfING MEMBER The present invention relates to a roofing member and whilst such might be provided as a modification to proper slates, the invention primarily relates to an artificial slate or a tile. Generally artificial slates are slate-like roofing members formed of other than slate, schwas of plastics material1 polymer material, cement material, ssh with water proofing or other material and such compositions are well known.

A disadvantage with slates and artificial slates results from the effect of moisture on roofing battens which tends to cause such to rot. The moisture may result from condensation on the lower surface of the slate which runs onto thebatten or may result from water being drawn between the adjacent surfaces of overlapping slates or artificial 8 slates by capillary action and this has a harmful effect on the roofing batten and also sometimes on the slate or artificial slate itself. This effect is particularly evident where two smooth flat surfaces are juxtaposed as with slates or artificial slates or flat tiles and where dust or other fine particles become disposed between the adjacent overlapping surfaces of slates or artificial slates.

For the sake of simplicity of description subsequent reference herein to "slate." is to be taken as meaning artificial.slates or to tiles. Wlth artificial slates, one or more small projections or nibs are provided adjacent the normally upper underside edge of the slate end each nib is in the form of a straight projection having right angled corners and being of rectangular cross section and said nibs are provided to engage the upper surface of a roofing batten to enable the slate to be hung thereon. However, such known nibs are prone to being broken off.

According to the present invention a roofing member, in the form of a slate or artificial slate or tile or like has at least one water drainage or ducting channel or groove on one surface extending in a direction from the normally upper edge or region of the slate or artificial slate towards the normally lower edge or region of the slate or artificial slate.

The main drainage groove or grooves will preferably be located so ss to divide the slate into two halves or into thirds or the like since the grooves may also be used to facilitate breaking of the slate into half or the like as is sometimes necessary.

Preferably each drainage groove has auxilIary drainage means on one or both sides in the form of fine grooves or scratches of lessee depth and width than the main drainage groove associeted therewith and being inclined at an acute angle to the main drainage groove extending over a short distance in an adjacent region downwardly into the associated main drainage groove to encourage the formation of condensation and flow thereof into the main groove.

Preferebly a plurality of such main drainage grooves are provided and preferably three grooves are equally spaced along the width of the slate.

It has been found that a drainage groove of approximately 1/8" depth and of approximately 3/16" width is suitable (and such applies to the capillary action prevention means mentioned below when in the form of a groove).

Also according to the present invention a roofing member, such as an artificial slate or a tile, has capillary action limiting or prevention means formed on or in the surface of the roofing member which is to be juxtaposed adjacent another roofing member such that, in use, water is prevented from moving upwards between two adjacent roofing member surfaces by capillary action.

The capillary action prevention means may be a projection or projections but is preferably a small channel or groove and such is preferably provided in a roofing member having one or more drainage grooves a. mentioned above.

Preferably, where a plurality of drainage grooves, preferably three1 are provided, at the normally lower end of each drainage groove an additional groove or recess is provided as said capillary action prevention means and preferably said capillary action prevention groove or recess interconnects the normally lower ends of the drainage grooves. Alternatively, the prevention means may comprise a circular recess at the bottom of each drainage groove and such recesses ay.partly overlap for interconnection, may have grooves interconnecting such or may be discrete and separate.

Also according to the present invention a roofing member such as a slate or artificial slate or tile has at least one suspension projection or hanging nib adjacent its upper edge wherein said nib has a first surface extending away, preferably at right-angles, from a first region of the normally underside of the slate or tile so as to be engageable for hanging over the normally upper surface of a roof batten, characterised in that 8 second surface or surfaces of said nib extends or extend from the normally underside or under upper edge of the slate or tile from a second reglon normally, in use, upwardly of said first region and extending to join the end of said first surface remote from the member to form a solid nib.Preferably, the second surface extends in straight-line or curved surface to the end of the first surface remote from the main under-surface of the roofing member normally upper edge of the slate or artificial slate. The formation of the nib or nibs preferably two nibs . so as to have other then rectangular cross section - preferably of triangular section in so far as it extends from the main body of the member - provides increased strength and a stronger construction. Preferably the nib or nibs will be integrally formed - preferably moulded - with the main rectangular body of the member. The improved nib according to the invention is considered inventive in its own right although may be used in combination with either of the two previously mentioned inventive aspects.

In either of the two previously described concepts according to the invention the lower edge and two side edges extending therefrom may be chamfered in known manner as existing slates.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which : Fig. 1 is a plan view of an artificial slate showing in broken-line grooves and features on the underside; Fig. 2 is a side elevation of the slate of Fig. 1; Fig. 3 is an end elevation of the slate of Fig. 1; Fig. 4 is a side elevation illustrating the slate hung and secured on a batten; Fig. 5 is a plan view of a slate with a preferred arrangement of nib shown in broken line; Fig. 6 is a schematic plan of En alternative embodiment; Fig. 7 is a perspective view of the underneath or belly of a tile forming an alternative preferred embodiment of the invention; Fig. B is a plan view of the tile of Fig. 7; and Fig. 9 is a section on the line X - X of Fig. 6.

In Figs. 1 to 6, an artificial slate 1 of suitable material is illustrated and is of rectangular shape and has chamfered edges 2 in known manner. The size of slate 1 will be selected as appropriate and will normally conform to known standard sizes.

The normally upper surface 3 is plane apart from edges 2 and nail holes 4 for nails 5 for securement in known manner on a batten 6. The face may have, however, a riven texture to give the appearance of real slate.

The normally under surface 7 of the slate 1 has three main condensation ducting or drainage grooves B 9, 10 extending parallelly from the region of a normally upper edge 11 towards the normally lower edge 92 and atop short thereof but run into a transverse groove 13 which acts as a capillary action prevention means end interconnects the bottom ends of grooves 8, 9 end 10. Instead of straight line transverse groove 13, circular or other shaped recesses may be provided as capillary action prevention means.

Along substantially the whole length of each side of grdwel 8, 9 and 10, much finer auxiliary ducting scorings or grooves 14 (only some being illustrated with respect; to groove 10) are provided inclined to each of the grooves 8, 9 and 10 to encourages toe flow of condensed moisture down- wardly therealong into main grooves 8, 9 end 10.

The grooves 8, 9 and 10 are disposed so as to divide the slate 1 into quarters and thus also facilitate breaking of the slates therealong as is sometimes required to make a slate fit.

At the normally upper edge 11, two nibs 15 are formed to enable the slate to be hung on batten 6. Each nib 15 comprises a suspension surface 16 extending at right angles from the normally under surface of the slate for sufficient distance and then joins an inclined face 17 extending to the normally upper edge 18 of the elate 1 as a continuous flat surface to form a solid nib which has increased strength as a result of the construction. The side faces 15' are inclined.

When the slates are laid the auxillary ducts 14 encourage the flow of condensing moisture into the main drainage grooves 8, 9 and 10 and the liquid then flows to transverse capillary action prevention groove 13 and thence downwardly and outwardly from the lower edge of the slates, providing for an improved roof and for improved slate life.

Various changes and modifications may be made without departing from the scope of the present invention. The dimensions in the drawings are not intended to be limitative.

Fig. 6 is a schematic underneath plan (showing the underside or "belly") of a slightly modified slate 1 wherein the grooves 8, 9, 10 are schematically indicated by broken line and some, but not all, of the finer auxillary condensation ducting scorings or grooves 14 are also schematically indicated. As regards the lower regions, circular recesses 19' are provided at the lower ends of grooves B, 9, 10 as condensation and capillary disposal points and interconnecting transverse groove 19 (schematically illustrated) extends across the lower region and through the recesses 18 as capillary action prevention means also. Alternatively webs 14 may be provided in place of grooves.

A preferred embodiment is illustrated in Figs. 7 - 9 and comprises a rectangular artificial slate or tile 20 of a rectangular standard shape and formed to have a substantially plain, normally upper surface 21 having an edge bevel in known manner and may possibly be provided with a surface appearance resembling that of a natural slate in known manner, i.e -have a riven texture on its face.

Figs. 7 and 6 show the normally lower side or "belly" of the slate 20 which has two projections or nibs 23 at the normally upper edge 24 of the belly. The nibs 23 have faces 23' remote from edge 24 and which are to abut a roof batten (not shown) for hanging of the slate in the manner as known with tiles. Faces 23' extend at right angles to the plane of the lower surface 25 of the slate 20 whilst the other side surfaces of the nibs 23 are inclined by being rounded as shown to provide increased strength with a top flat portion.

The belly of the slate can be regarded as having a number of surface portions lying in the same plane and having a number of recessed portions or portions of reduced thickness wherein the bases of the recessed portions lie in the same plane i.e. the reduced thickness portions are generally of the same thickness. 11 The belly 22 comprises a central rib 26 having a ventilation-drainage channel 27 therein leading from an upper region, where it terminates short of edge 24, to a generally circular recess 28 in a lower region. The main function of channel 27 is to drain the central region of the slate although it may also act to ventilate such. In a modified arrangement (not shown) the channel 27 may communicate with adjacent drainage-ventilation recesses to improve ventilation.

Two further ventilation-drainage channels 29, 30 are provided on the belly and lead, via generally circular recesses 31, 32, to a transverse channel or groove 33 near the normally lower edge and which in effect extends from a lower region of the recesses 28, 31, 32, which may be of any suitable shape and provide an enlargement in the channel and/or groove. The groove 33 which extends across the bottom of the slate 20 from edge region to edge region and through central recess 28. The groove 33 has its bottom surface on the same level as the bottom surface of the recesses 28, 31, 32. The groove 33 acts to prevent water being drawn up by capillary action with the surface of a slate beneath and this acts as a weather bar and also acts with the grooves 28, 31, 32 in the assistance of ventilation of the slate region therebelow when in its position of use.

Four spaced apart webs or deflection potions 34, 35 and 36, 37 extend inclinedly downwards from rib 26 preferably at an angle of 450 thereto and terminate at a distance from the surrounding rim 38 of the slate so as to form part of said channels 29, 30. The deflection portions 34 - 37 have their normally lower surface (the upper surface as viewed) in the same plane which is the same as the plane in which lie the rim 38 and the normally lower surface of rib 26.

The deflection portions 34 - 37 apart from providing strength to the slate, also act to deflect any condensed water outwardly to generally circular recesses 31, 32 and also facilitate circulation of air for ventilation purposes. The preferred disposition of deflection portions 34 - 37 at 450 provides a guide surface which facilitates cutting of the slates at 450 which is often required in roofing.

A further deflection and reinforcement portion 39 is provided on either side of rib 26 with walls preferably inclined at 450 and leads into walls 40 forming one side wall of groove 33. Portions 39 and walls 40 are in the same plane as the normally lower surface 18.

Recessed portions 41 - 46 are thus formed for the formation and/or collection of condensation and for ventilation purposes. Short ventilation-drainage grooves 47, 48 extend in the enlarged upper rim portion 18' from the end faces 23' of the nibs 23 into the recessed portions 43, 44 respectively to facilitate ventilation and/or drainage of the rib region which is particularly prone to damage from damp. Two holes 49 are provided in the slate for securing nails (not shown).

The provision of the ventilation-drainage channels leading to the lower corner regions with half-bending of slates, results in any water drained from thgunderside of a slate being deposited on the centre of a lower slate rather than in the edge regions.

Each of the deflection portions 34, 35, 36 and 37 preferably has two additional ventilation-drainage channels 50 extending therethrough and running parallel to channels 29 and dividing the deflection portions into equal segments.

The additional channels 50 provide increased drainage and ventilation effect.

It is to be appreciated that various modifications and changes can be effected without departing from the scope of the present invention. For example, the number or shape or spacing of the deflection ribs may be changed as described. Furthermore, for larger slates, two or more main ribs (similar to 26) may be provided and the adjacent ends of the deflection ribs will be spaced to permit the drainage of water and ventilation. It is to be appreciated that whilst reference is made to a ventilation-drainage groove, such as shown in Fig. B is not a continuous groove as such but rather at least one drainage means or recess leading into lower recess forming the weather bar. Interlock connections may be provided in known manner to connect with adjacent slates.

The roofing member is self-ventilating and selfdraining.

A reduction in material required is achieved whilst still retaining strength.

Claims (1)

1. A roofing member, in the form of a slate, artificial slate, tile or like generally flat, rectangular member having at least one ventilation drainage recess on the normally lower surface and extending from a normally upper edge or region of the member towards the normally lower edge or region of the member where said ventilatios drainage recess runs into a groove or recess extending across the normally lower edge region of said member and acting as capillary action limiting or prevention means which also facilities ventilation.

2. A member as claimed in claim 1, in which the ventilation recess is a main drainage groove or grooves located so as to divide the slate into two halves or into thirds, quarters or the like wherein the grooves also function to facilitate breaking of the slate in half or into thirds, quarters or the like.

3. A member as claimed in claim 1 or 2, in which each ventilation-drainage recess has auxillary drainage means on one or both sides in the form of webs or of fine grooves or scratches of lesser depth and width than the main drainage groove, associated therewith and being inclined at an acute angle to the main drainage groove extending over a short distance in an adjacent region and, in use, downwardly into the associated main drainage groove to encourage the formation of condensation and flow thereof into the main groove.

4. A member as claimed in any of claims 1 to 3, in which a plurality and preferably three, main drainage grooves are provided equally spaced across the width of the member.

5. A member as claimed in any of claims 1 to 4, in which a main drainage groove of approximately 1/8" depth and of approximately 3/16" width is provided.

6. A member as claimed in any of claims 1 to 5, in which capillary action limiting or prevention means, preferably in the form of a recess and preferably a transverse groove, is provided in the normally underside and lower half of the member and is to be juxtaposed adjacent another,lower roofing member such that, in use, water is prevented from moving upwards between the two adjacent roofing member * surfaces by capillary action.

8. A member as claimed in any of claims 1 to 7, in which a plurality of drainage grooves, preferably three, are provided and at the normally lower end of each drainage groove an additional groove or recess is provided as said capillary action prevention means and, preferably, said additional groove or recess interconnects the normally lower ends of the main drainage grooves.

9. A member as claimed in claim 8, in which the additional recess is a circular recess at the bottom of each drainage groove and such recesses overlap for interconnection or have grooves interconnecting such or are discrete and separate.

10. A member as claimed in claim 1, in which a ventilationdrainage channel is provided leading from each rib in a direction towards the normally lower edge of the member.

11. A member as claimed in claim 1, 6 or 10, in which the or each ventilation-drainage recess is provided with at least one deflection portion inclined so as to direct any water condensed on the underside of the member to a part of the ventilation drainage recess leading to said lower transverse groove or channel.

12. A member as claimed in claim 11, in which each said deflection portion is inclined relative to the longitudinal axis of the member at 45 or other angle as will facilitate guidance for cutting of the member if required.

13. A member as claimed in claim 11 or 12, in which said ventilation-drainage recess is divided by said deflection portion(s) into large recess portions interconnected by smaller recess portions leading towards said lower transverse groove.

14. A member as claimed in claim 1 or any of claims 10 to 13,inwhichintheregion where each said ventilation drainage groove joins said lower transverse groove an enlarged recessed portion is provided, preferably of generally circular autline or shape and interconnects each said ventilation-drainage groove with said transverse groove.

15. A member as claimed in claim 1 and any of claims 10 to 14, in which a rib extends from the region of the upper edge to the region of the lower edge of the member and preferably has a ventilation-drainage channel extending therealong and running into said lower transverse groove, preferably via an enlarged recess portion preferably of circular shape.

16. A member as claimed in any of claims 10 to 15, in which said rib is centrally disposed and has on either side two inclined deflection portions extending therefrom to deflect any condensed water outwardly to ventilation drainage recesses leading to said lower transverse groove.

17. A roofing member substantially as herein described with reference to the accompanying drawings.

18. A member as claimed in any of claims 11 to 17 in which one or more, preferably two, additional ventilationdrainage channels are provided in each deflection portion.