GB2307922A

GB2307922A - Roof valley unit

Info

Publication number: GB2307922A
Application number: GB9618355A
Authority: GB
Inventors: Norman J Pugh
Original assignee: Hambleside Danelaw Ltd
Current assignee: Hambleside Danelaw Ltd
Priority date: 1995-11-23
Filing date: 1996-09-03
Publication date: 1997-06-11
Anticipated expiration: 2016-09-03
Also published as: GB2307922B; GB9523934D0; GB9618355D0

Abstract

A roof valley unit (8) and a method of installation of roof valley units at valleys between pitched roof sections (9, 10). The roof valley unit lateral wing portions (1, 2) which extend from respective sides of a longitudinally extending upstanding portion (3). Each wing portion (1, 2) has a lateral margin in the form of a flat sheet area which is capable when installed in a roof valley of being positioned beneath an end region of a batten (16, 17) fixed to the roof. Each wing portion (1, 2) may be provided with a longitudinally extending raised portion (4, 7) intermediate the upstanding portion (3) and the lateral margin of the wing portions (1, 2). The upstanding portion (3) may comprise opposed walls interconnected at an apex which is capable of acting as a hinge.

Description

ROOF VALLEY UNITS The invention relates to roof valley units for installation at valleys between pitched roof sections.

Many buildings have a roof consisting of a plurality of overlapping shingles or coverings, for example slates or tiles. The shape of the roof and the overlapping of the shingles provides suitable drainage for precipitation. Conventional roofs have a support frame comprising inclined rafters meeting together at a ridge and supported at their lower ends on wall plates. The lower ends of the rafters are frequently tied together by cross beams to define an A frame or truss. Adjacent trusses or A frames are spanned by transversely extending battens which constitute the immediate support for the roof cladding elements, which are typically secured to the battens by fixings, usually pins or nails, driven through the cladding elements into the battens.The pattern of fixing roof cladding elements from the ridge to the eave typically comprises rows of staggered shingles, generally offset by one half their width from adjacent overlying and underlying rows.

Where two pitched roof sections meet a valley is created at the intersection which cannot easily be covered with cladding. This valley must be made watertight.

Conventially, this is done by laying a row of trough tiles up the valley and filling the gaps between the trough tiles and the edge shingles or coverings of the adjacent roof sections with cement mortar. The edge shingles have to be cut at an angle. In more recent times, one or more elongate strips of suitably formed plastics material, possibly reinforced with glass fibres, have been used instead of the trough tiles, but the gap between this material and the edge tiles still needs to be filled with cement mortar.

Such elongate strips or troughs may have a generally V or U shaped cross-section and are commonly known as valley troughs or strips.

The operation of filling the gaps with cement mortar is time-consuming and should not be performed in wet or frosty weather. It is unfortunately a common practice for excess mortar to be applied, resulting in spillage and possibly blocking of the trough.

It has therefore been much desired to construct valleys without using mortar (or "dry"), especially since all other roof areas can normally constructed without mortar.

To that end, various proposals have been made for "dry" valley troughs.

Valley troughs may be laid along the roof valley and attached to roof battens by pinning at their edges. Shingles are laid on top of the longitudinal edges of the valley trough. Thus some drainage and weather protection is provided at roofing section valleys. However, existing dry valley troughs have encountered problems in use and, despite considerable efforts to design acceptable dry valley troughs, an acceptable structure has not hitherto been found. A particular difficulty has been the transverse movement of water and debris such as leaves across the trough and under the shingles.

If wet leaves collect beneath the shingles they will tend to cause a gradual decay in the roof by, for example, rotting the rafters or battens. This is a particular problem with tiled roofs since tiles generally have a thickness of the order to 2 cm, in contrast to thinner slates. When tiles are laid in the usual overlapping relation with one another, a relatively large gap is created beneath the tiles at the edge of the roof section at the step between one tile and its overlying neighbour. This gap can allow water and debris to collect beneath the tiles.

In an endeavour to enable valley units to be installed without mortar, designs have been made in which upstanding walls have been provided on either side of a central trough channel and shaped to provide a laterally facing longitudinal slot for receiving the edges of the shingles adjacent the valley. The upstanding walls are typically provided with through holes to permit water, but not large debris, to pass into the central channel. None of the "dry" valley units made hitherto has proved to be successful. Some designs have combined a propensity to let water and debris go under the shingles with a multi-part construction or a configuration which could have been especially designed not to be stackable.

GB 1 409 732 discloses a gulley comprising an elongate member of waterproof material with a central upstanding member and a masking member. There is a channel either side of the central member formed from flanges extending laterally from the central member.

GB 2 211 867 discloses a valley trough comprising an elongate section having generally a shallow V shaped cross-section with an upstanding abutment extending longitudinally along the section substantially in the longitudinal centre. A gutter is located on each side of the abutment.

The prior art teaches the use of valley troughs to replace traditional methods explained above. However, there are problems associated with such use not disclosed in the prior art. For example a roof valley unit must be universal in application because of the wide selection of roof coverings and the requirement to fit with variable roof pitches and sizes. Secondly, for a valley unit to function, it must be adapted to provide drainage for both the roof covering and the under layer, e.g. felt, without deteriorating those materials. For example capillary attraction in felt is a common factor in its deterioration at soak away points. The prior art does not provide solutions to these problems.

By contrast the present inventor has, by going in a direction contrary to conventional thought, designed a "dry" valley unit which has proved successful in in situ trials even though it dispenses with features previously considered essential, such as a central channel to carry all the valley water In one embodiment, the present invention provides a roof valley unit comprising lateral wing portions extending from respective sides of a longitudinally extending upstanding portion, each wing portion having a lateral margin in the form of a flat sheet area capable, when installed in a roof valley, of being positioned beneath an end region of a batten fixed to the roof Preferably, the upstanding portion comprises opposed walls interconnected at an apex which is capable of acting as a hinge. The hinge means may be capable of allowing opposed walls to contact each other.

The roof valley unit is preferably made in one piece. It is normally made of plastics material, for example extruded plastics material, and preferably with a low co-efficient of expansion, for example 20 x 104 m/m per "C, reinforced by glass or other fibre.

Alternatively, the roof valley unit is made of GRP (glass reinforced plastics - e.g. glass reinforced polyester) by a pultrusion process.

In one class of embodiments, the roof valley unit is made of flexible material.

Each wing portion is preferably provided with a longitudinally extending raised portion, e.g. a rib, intermediate the upstanding portion and the lateral margin of the wing portion. Preferably, each wing portion is provided with two, or possibly more than two, such raised portions in laterally spaced relationship.

The upstanding portion is preferably of such a height that it will extend above adjacent coverings when the valley unit is incorporated in a roof valley. Roof valley units having upstanding portions of different heights may therefore be made for tiles and slates. For tile roofs, the upstanding portion preferably has an apex at least 5 cm above the highest area of the wing portions, which usually means at least 5 cm above the raised portions (ribs) of the wings, preferably, the apex of the upstanding portion is at least 6 cm above the highest area of the wing portions (e.g. 6-7 cm) and is suitably about 6.5 cm thereabove. For slate roofs, whether of natural or artificial slate, the upstanding portion is desirably lower and preferably 4-5 cm e.g. 4.5cm or more.

Roof valley units made of flexible plastics material may have wing portions which are generally planar in orientation when not flexed. The wing portions are capable of being flexed to a suitable relative angle when the unit is attached to a roof valley. In other embodiments the roof valley units are manufactured with wing portions which are oriented upwardly and outwardly.

The roof valley units of the invention are preferably stackable, but this is not essential.

In one class of embodiments, the roof valley unit is capable of being lapped at its ends by another said roof valley unit.

The invention also includes a roof valley strip, comprising a sole having first and second ends and opposed sides, the sole being provided in a central region thereof with raised barrier means extending between said first and second ends, and having on each side of the barrier means a lateral portion for forming a channel for water and a flat margin, the channel base and flat margin of each lateral position being capable of lying generally in a common plane.

Optionally, the roof valley strip of the invention is a corrugated plastics sheet having a central corrugation which constitutes the raised barrier means and in each lateral portion a corrugation defining the channel. Preferably, each lateral portion has two, or possibly more than two corrugations The invention further includes a method of making a roof valley unit or strip of the invention, comprising extruding plastics material through an extrusion die shaped to extrude a said roof valley unit or roof valley strip. It includes a method of making a roof valley unit or strip of the invention from GRP (glass reinforced plastics e.g. glass reinforced polyester) by a pultrusion process.

In another aspect the invention provides a method of installing on a roof area a roof valley unit or strip of the invention wherein the roof valley unit is located in the valley between two pitched roof sections and fastened to the roof area. Typically, a central region of the unit or strip is pushed to the bottom of the valley such that the wings or margins flex in an upward and outward direction and the sides of the upstanding portion or, as the case may be, the barrier means are brought into contact with each other.

A preferred option is for the roofing underfelt to be cut to finish between the two raised portions or corrugations where applicable. The battens are connected to the roof and may overlay the roof valley units or strips.

Preferably, roof coverings are applied such that edges of the coverings abut or juxtapose the upstanding.portion of the roof valley unit or the barrier means of the roof valley strip, which edges may have been cut as necessary prior to the roof coverings being applied.

The present invention is further described by way of example only with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a roof valley unit of the invention; Figure 2 is a schematic cross section through a roof valley incorporating the roof valley unit of Figure 1; Figure 3 illustrates a partially constructed roof valley incorporating the roof valley unit of Figure 1; and Figure 4 is an end elevation of a second roof valley unit ofthe invention.

Figure 1 illustrates a roof valley unit comprising lateral wings 1, 2 extending from respective sides of a longitudinally extending upstand 3, each wing having a lateral margin in the form of a flat sheet area capable, when installed in a roof valley, of being positioned beneath an end region of a batten fixed to the roof The upstanding portion comprises opposite walls interconnected at an apex capable of acting as a hinge which allows opposed walls to contact each other when in use.

In the illustrated embodiment the roof valley unit is made of flexible plastics material, which is desirably fibre-reinforced. It is most preferred that the unit be made of GRP (e.g. glass reinforced polyester) material, formed by pultrusion into an elongate strip.

The roof valley unit is preferably made in one piece.

The wings 1, 2 of the flexible unit shown in Figure 1 have an approximately planar orientation in the unflexed state. Alternatively, the wings 1, 2 are raised towards their free edges; for example, they may be angled upwardly from the base of the upstand 3.

In one class of embodiments the lateral edge portion of each wing is elevated.

The wings 1, 2 of preferred embodiments are each provided with at least one longitudinally oriented raised portion spaced from the upstand 3. Thus, Figure 1 shows that each wing 1, 2 has two longitudinally extending and spaced apart ribs 4, 5, 6, 7. The wings 1, 2 ofpreferred units have flat (not raised) side margins 20, 21.

Figure 2 is a schematic drawing which shows a dry valley strip of Figure 1 in position in a valley between two pitched roof sections. The roof valley unit or strip is indicated by numeral 8. The Figure shows inclined rafters 9, 10 behind which a series of spaced apart rafters (not shown) form frameworks for the roof sections.

Layboards 11, 12 are shown to be disposed on the rafters 9, 10. Each layboard 11, 12 comprises an elongate wooden board extending over and supported by a multiplicity of rafters. The use of layboards in roof valleys incorporating a dry valley strip of the invention is optional but preferred.

A section of roofing felt 13 is preferred to be laid over the layboards 11, 12 but may be dispensed with. The roof valley unit 8 is seated over the felt 13. During installation, the roof valley unit 8 was pressed firmly into place such that the centre of the unit 8 (the base of the upstand 3) was pushed into the bottom of the valley and the wings 1, 2 flexed upwardly from the upstand 3; the roof valley unit 8 was then nailed into position. The roof valley unit 8 it sill forms a trough divided into two channels by a dam formed by the upstand 3. Preferably, the upstanding portion walls (20, 21) are brought into contact with each other by the use of the hinge 3a so the unit is in a state of tension before the roof valley unit is nailed into position.

In the illustrated arrangement sections of roofing felt 14, 15, each on a respective pitched roof section, each have an edge portion overlying an edge portion of a respective wing 1, 2 of the roof valley unit; the roofing felt sections 14, 15 extend over the laterally outer ribs 4, 7 ofthe roof valley unit.

Battens 16, 17 are seen to have end regions overlying side margins 20, 21 of each wing 1, 2 as do successive battens (not shown) of each roof section. The battens 16, 17 support tiles 18, 19. The upstand 3 preferably stands proud of adjacent tile edges.

Figure 3 shows a roof valley in the course of construction. Roofing felt 13 obscures underlying layboards and is in turn covered by a roof valley strip 8 secured to rafters 9, 10. Further sections of roofing felt 14, 15 have edge portions each overlying an edge portion of a respective roof valley wing 1, 2. Battens 16, 16', 17, 17' have been cut to size for their ends to extend over the flat side margins 20, 21 (or fixing strip) of the roof valley unit 8 and been fixed at their ends by nailing to the supporting layboards.

After the felt and battens have been secured to the roof frame, shingles are applied, their edges adjacent the valley being cut to abut or juxtapose the upstand 3. The upstand 3 is able to withstand small cuts therein.

In use, the upstand 3 acts as a barrier to resist passage of water and debris across the unit 8. Water and debris leaving the edge of a tile, such as tiles 18 and 19, are normally prevented by the upstand 3 from traversing to the opposite side of the valley from that on which the tile is located. Separate channels are formed on each side of the upstand 3, with the ribs 4, 5, 6, 7 as well as the inclined wings 1, 2 serving substantially to prevent water escaping sideways from the channels 1, 2.

It is important for the underfelt to be cut to finish over and within the outer channel created by the two corrugations in order so that the channels can collect moisture from the underfelt and avoid capillary attraction which would cause deterioration of the felt.

It will be appreciated that the upstand 3 preferably stands proud of the shingles, for the purpose of preventing water or debris leaving a roof section on one side of the upstand 3 and traversing the valley strip to the opposite side of the upstand 3. For tile roofs, it is preferred for the upstand to have an apex about 6-7 cm, e.g. 60.5 cm, above the highest area of the wings. The upstand may be higher than 7 cm but a greater height is excessive for ordinary tile roofs and not preferred. A lesser height may be acceptable, eg. 5 cm.

Figure 4 is a partial end elevation of a preferred embodiment of the invention adapted for a tile roof. The undersides of the tiles rest on the apex of the outer rib 4. The separation y between the apex of the rib 4 and the upper surface of the wing 1 where it is not elevated is about 1.5 to 3 cm, e.g. about 2 cm.

The separation x between the apex of the rib 4 and the apex of the upstand 3 is preferably between 6 and 7 cm, most preferably about 6.5 cm. The width of the roof valley unit is typically between 30 and 50 cm and more preferably between 35 and 40 cm, e.g. 37 cm.

The inner rib 5 is slightly lower than the outer rib 4 in the illustrated embodiment, but such a configuration is not essential.

In trials, it has been proved that the invention enables provision of"dry" valley strips which are effective in draining roof valleys without any noticeable water entering the structure of the roof. Not only is movement of water and debris across the valley strip controlled, but also the strip lacks the debris traps of some prior art proposals; moreover entry of debris into the water channels defined by the valley strip is normally restricted by a small separation between the upstand and adjacent shingle edges.

The unit should be universal in its application so that it will fit variable roof pitches and adapt to various roof coverings Optionally, the unit can be manufactured into standard lengths being cut to the correct lengths in situ. The profile of the unit should enable overlapping end to end to form a close fitting joint.

The upstand 3 of preferred embodiments provides increased strength to the valley strips or units of the invention by the shape of the upstand and the state of tension it is under and protects against damage to the valley by feet during construction or maintenance of a roof. The upstand also maintains an aesthetically pleasing straight line appearance to a roof valley, regardless of badly cut tiles. The roof valley strips of preferred embodiments are readily stacked.

It will be seen that the present invention provides a roof valley strip, comprising a base having first and second ends and opposed sides, the base being provided in a central region thereof with raised barrier means extending between said first and second ends, and having on each side of the barrier means a lateral portion for forming a channel for water.

The invention enables provision of such a roof valley strip which is stackable.

Claims

CLAIM S

1. A roof valley unit comprising lateral wing portions extending from respective sides of a longitudinally extending upstanding portion, each wing portion having a lateral margin in the form of a flat sheet area capable, when installed in a roof valley, of being positioned beneath an end region of a batten fixed to the roof.

2. A roof valley unit of claim 1 wherein the upstanding portion comprises opposed walls interconnected at an apex capable of acting as a hinge.

3. A roof valley unit of claim 2 wherein the hinge means is capable of allowing opposed walls to contact each other.

4. A roof valley unit of claims 1 to 3, which is made in one piece.

5. A roof valley unit of claims 1 to 4, which is made of flexible material.

6. A roof valley unit of claim 5, wherein the flexible material is a plastics material with low co-efficient of expansion, for example fibre reinforced plastics.

7. A roof valley unit of claims 5 or 6 wherein the flexible material is GRP (e.g.

glass reinforced polyester).

8. A roof valley unit of any of claims 5 to 7, wherein the wing portions are generally planar in orientation when not flexed.

9. A roof valley unit of claim 8, wherein the upstanding portion has an apex at least 4.5cm above the highest area of the wing portions.

10. A roof valley unit of claim 9, wherein the upstanding portion has an apex about 6-7 cm above the highest area of the wing portions.

11. A roof valley unit of any of claims 1 to 7, wherein the wing portions are orientated upwardly and outwardly.

12. A roof valley unit of any of claims 1 to 11, wherein each wing portion is provided with a longitudinally extending raised portion intermediate the upstanding portion and the lateral margin of the wing portions..

13. A roof valley unit of claim 12, wherein each wing portion is provided with two said raised portions in laterally spaced relationship.

14. A roof valley unit of any of claims 1 to 13, which is stackable.

15. A roof valley unit according to any of the preceding claims which is capable of being lapped at its ends by another roof valley unit.

16. A roof valley strip, comprising a sole having first and second ends and opposed sides, the sole being provided in a central region thereof with raised barrier means extending between said first and second ends and having on each side of the barrier means a lateral portion for forming a channel for water and a flat margin, the channel base and flat margin of each lateral position being capable of lying generally in a common plane.

17. A roof valley strip of claim 16, which is a corrugated plastics sheet having a central corrugation which constitutes the raised barrier means and in each lateral portion a corrugation defining the channel.

18. A roof valley strip of claim 17, wherein each lateral portion has two corrugations.

19. A roof valley unit substantially as hereinbefore described with reference to or as illustrated in the accompanying drawings.

20. The use of a roof valley unit of any of claims 1 to 15 or 19 or of a roof valley strip of any of claims 16 to 18 to construct a mortarless roof valley.

21. A mortarless roof valley comprising a roof valley unit of any of claims 1 to 15 or 19 or a roof valley strip of any of claims 16 to 18 whose margins are disposed beneath roof coverings edging the valley and which is secured to the roof frame.

22. A roof valley of claim 21, wherein the upstanding portion of the roof valley unit or, as the case may be, the barrier means of the valley strip stands proud of the covering edges adjacent thereto.

23. A roof valley of claims 21 to 22 which comprises a roof valley unit as defined in claim 2 or a roof valley strip as defined in claim 17 and wherein the sides of the upstanding portion of the roof valley unit or, as the case may be, the barrier means of the valley strip are in contact with each other at a base region thereof

24. A method of making a roof valley unit of any of claims 1 to 15 or 19 or a roof valley strip of any of claims 16 to 18, comprising extruding plastics material through an extrusion die shaped to extrude a said roofvalley unit or roof valley strip.

25. A method of making a roof valley unit of any of claims 1 to 15 or 19 or a roof valley strip of any of claims 16 to 18, comprising pultruding GRP.

26. A method of installing on a roof area a roof valley unit according to claims 1 to 15 or 19 or a roof valley strip of any of claims 16 to 18, wherein the roof valley unit is located in the valley between two pitched roof sections and fastened to the roof area.

27. A method according to claim 26, wherein a centre region of the unit is pushed to the bottom of the valley such that the wings or, as the case may be, the margins flex in an upward and outward direction and the sides of the upstanding portion or, as the case may be, the barrier means are brought into contact with each other.

28. A method according to claim 27 wherein roofing underfelt is cut to finish between two raised portions on each wing portion or, as the case may be, between two corrugations on each lateral position..

29. A method according to claims 27 to 28 wherein battens are connected to the roof to overlay said roof valley units or, as the case may be, roof valley strips.

30. A method according to claim 27 to 29, wherein roof coverings are applied to the roof area such that edges of the coverings abut or juxtapose the upstanding portion of the roof valley unit or, as the case may be, the barrier means of the roof valley strip, which edges may have been cut as necessary prior to the roof coverings being applied.