AU2016262673B2 - Roof flashing with rainwater diffuser - Google Patents

Abstract

A diffuser 15 is attached to the front of roof penetration flashing 14 to even out water flow about the flashing such that water flows more evenly into the pans/valleys of the roof sheets downstream from the flashing. FIG 3 FRONT DIFFUSER INSTALLED 26 23 26 26

Description

ROOF FLASHING WITH RAINWATER DIFFUSER TECHNICAL FIELD

The present invention is directed to roof flashings to weatherproof penetrations and which better direct rainwater about the flashing. The invention is also directed to a diffuser which can be attached to flashing to better direct rainwater about the flashing.

BACKGROUND

Any references to methods, apparatus or documents of the prior art are not to be taken as constituting any evidence or admission that they formed, or form part of the common general knowledge.

It is often necessary for various objects to proceed through a roof. The objects can include vent pipes, different types of ducting including air-conditioning ducting, light domes, skylights, roof ventilators (whirlybirds) and the like. Such objects are collectively known as “penetrations” or “roof penetrations” as they pass through openings cut or otherwise formed in the roof sheets. The opening itself in the roof is also frequently referred to as a “penetration”.

To prevent water from passing into the opening cut into the roof, the penetrations are waterproofed by a weather resistant barrier (WRB). These barriers are often known as “flashing”.

Flashing refers to thin pieces of impervious material installed to prevent the passage of water into a structure from a joint or as part of a weather resistant barrier (WRB) system. Metal flashing materials include lead, aluminium, copper, stainless steel, zinc alloy, other architectural metals or a metal with a coating such as galvanized steel, lead-coated copper, anodized aluminum, galvalume (aluminum-zinc alloy coated sheet steel), and the like. Nonmetal flashings are also known.

In commercial buildings or other large roofing areas, it is common for the roof to have only a very slight pitch. The roof is essentially flat with only a slight incline (sometimes only about 1°). To prevent water seeping through overlapping roof sheets, the sheets have a high profile with upstanding ribs. Adjacent sheets overlap over the rib area. The area between the ribs (often called a pan or valley) channels water off the roof.

Other buildings have a greater roof pitch allowing corrugated metal roof sheets to be used. Alternatively, concrete tiles can be used. A problem with some flashings about roof penetrations is that rainwater must flow over the roof from behind (upstream) the flashing, over part of the flashing and back onto the roof in front (downstream) of the flashing. PRIOR ART figure 1 illustrates this arrangement. Figure 2 illustrates the particular problem with this arrangement. In figure 2, the flashing 10 extends over eight pans 1-8. Water flowing down pans 1-8 behind the flashing must flow to each side of the flashing and over each side flange 11 -12 of the flashing. Thus, the amount of water 13 flowing over each side flange 11-12 is four times the volume flowing down each pan 1-8 behind the flashing. When this condensed stream flows over the side flanges 11-12 and back into the downstream pans, most of the water will flow into pans 1-2 and 7-8 and not pans 3-6. This can cause roof drainage problems due to uneven flow along all the pans of the roof sheets. Also, sometimes the roof penetration extends through a join where two roofing sheets overlap each other. High flow volumes along a pan adjacent an overlap between two roofing sheets can cause water to seep through the overlap and into the interior of the building.

These problems are present for commercial metal roofing having a low pitch. However roofs with a steeper pitch and comprising corrugated roof sheets also suffer from this problem, as do tile roofs where too high a water volume flow can cause leakage between tiles.

It is an object of the invention to provide a solution to uneven water flow over a roof penetration flashing or other flashings that suffer from the same disadvantage.

SUMMARY OF THE INVENTION

In one form the invention comprises at least one water diffuser adapted to catch water flowing along at least one side of roof penetration flashing and to more evenly spread the water along the front of the flashing to facilitate even roof drainage wherein the diffuser comprises an elongate upstanding wall, a positioning arrangement to removably position said upstanding wall across the front of the flashing to catch the water flowing along at least one side of the roof penetration flashing, wherein at least part of said wall is spaced apart from the flashing such that water can flow therebetween.

In another form, the invention comprises penetration flashing comprising at least one water diffuser adapted to catch water flowing along at least one side of the flashing and to more evenly spread the water along the front of the flashing to provide more even roof drainage.

In this manner, the diffuser can function to spread the condensed water flowing along each side of the flashing back into a more even flow to pass more evenly into each of the pans, valleys etc. in front of the roof penetration.

There is much less likelihood of water overflowing a particular pan and possibly leaking into the roof (especially if there is an overlap between roof sheets), and the water is drained more evenly into a collection gutter which can also reduce the possibility of gutter overflow.

Suitably the, or a, diffuser catches water flowing along each side of the flashing. It is envisaged that in most cases, the roof penetration will contain flashing adjacent each side and in these circumstances it is preferred that the diffuser catches water (that is "condensed" water) flowing along each side of the flashing and spreading the water more evenly into all the downstream pans/valleys etc.

Suitably, the diffuser comprises part of the flashing. It is considered that the flashing can be shaped or configured to comprise part, or all of the diffuser. However, it is also envisaged that the, or parts of the diffuser may comprise at least one separate item that can be attached to part of the flashing or adjacent the flashing or otherwise be associated with the flashing to more evenly spread the water along the front of the flashing to provide more even roof drainage.

The diffuser may be configured to cause water to flow more into the pans or valleys of the roof sheets or members and less onto the ridges of the roof sheets or roof members. It is considered more efficient if the diffuser can be configured to divert water flow directly into the pans or valleys of the roof sheets or tiles etc. as opposed to the ridges. The ridges may comprise fastening screws and water may leak into the interior past the fastening screws. Therefore, it is considered advantageous if the diffuser is configured to divert water as much as possible away from the ridges of the roof sheets.

The penetration flashing can be used to flash various different types of penetrations which will usually include air-conditioning ducting (especially for commercial roofing), vent pipes, whirlybirds and similar devices, skylights and the like. There may be circumstances where there is an advantage in providing a water diffuser on roof flashing that comprises other than penetration flashing to more evenly spread water flow along the roof. There may be circumstances where there is an advantage in providing a water diffuser on other types of flashing to more evenly spread water flow along the roof.

The penetration flashing will typically comprise a rear panel, a front panel and a pair of side panels. An upright collar portion is typically provided. The collar portion may comprise part of each panel or may be formed separately. The panels may also comprise separate pieces attached to each other or parts of the penetration may comprise a common flashing. For instance, one piece of flashing may be substantially U-shaped to comprise the back panel and each side panel and a second piece of flashing may comprise the front panel.

For circular penetrations, the flashing may be as described above except that the upright collar portion will be circular. Flowever, the flashing itself may also be substantially circular or have other shapes.

The flashing will typically comprise metal flashing but there may be circumstances where plastic flashing or other types of flashing may be suitable.

The flashing will typically comprise a number of separate pieces joined together in the usual manner which may comprise fasteners such as screws or rivets and/or silicone adhesive or other types of adhesive.

The diffuser will typically be positioned at, or substantially adjacent a front edge of the front panel. Suitably, the diffuser will extend substantially along the front edge of the front panel. In a preferred embodiment, the diffuser extending along the front edge of the front panel comprises a single elongate member. The length of the member can vary depending on the width of the front panel of the flashing. As it is envisaged that the front panel will typically have a length of between 50-250 cm, it is envisaged that the diffuser will also have a length of between 50-250 cm.

It is also envisaged that the diffuser may comprise a plurality of smaller elongate members. It is also envisaged that the diffuser may comprise a telescopic member that can be extended to the desired length. The diffuser may be cut to length.

The diffuser may comprise any suitable material. Suitably, the diffuser will be made of material similar to the flashing material and thus will typically comprise metal treated for corrosion resistance. Flowever, the diffuser may also be made of plastics material

The diffuser may comprise at least one upstanding wall adapted to catch water. The upstanding wall will typically have a height sufficient to prevent water from simply flowing over the top of the wall under usual water flow conditions. The height will be dependent, inter alia, on the flow volumes about each side of the flashing and this can be calculated. The height of the upstanding wall may be sufficient to catch water flow from the largest type of flashing and an advantage of this arrangement is that the diffuser will not require many different types of wall heights. It is envisaged that for most flashings a suitable wall height will be between 50-250mm.

The upstanding wall may be height adjustable to accommodate different water flow volumes and velocities. In one form, an extension wall or panel may be attached to the upstanding wall to increase the wall height. The extension panel may extend substantially along the upstanding wall, or may extend only at places where there is increased risk of water quickly overflowing the existing upstanding wall. Thus a plurality of extension panels may be provided.

The water diffuser may be provided with attachment means to enable the diffuser to be attached to part of the flashing or to somewhere else to enable the diffuser to function efficiently. It is considered expedient that the diffuser is attached to the flashing and preferably adjacent the front edge of the front panel of the flashing. A plurality of attachment means may be provided to enable the diffuser to be attached to the flashing at a plurality of positions.

The attachment means may comprise a tab member. The tab member may comprise part of the diffuser which is bent or otherwise configured to provide the tab member. The diffuser will typically comprise a plurality of spaced apart tab members. The members are suitably spaced to overlie the ridges of a roof sheet. The tab members may be formed separately and fastened by any suitable means to the remainder of the diffuser. As an example, the tab members may be fastened in place and the remainder of the diffuser may be clipped or press locked or otherwise attached to the tab members. This can assist in divert in rain water away from the roof sheet ridges and into the roof sheet pans. Thus, the tab member may comprise a combined function of fastening the diffuser in place - typically on the flashing - and also functioning as a deflector to deflect water away from the ridge of the roof sheets. This will be described in greater detail below.

The attachment means may be associated with at least one, and preferably a pair of bracket members. These can function as strengthening members to prevent twisting or bowing of the diffuser. The bracket members can also function to guide rain water into the roof pans.

The diffuser may comprise a secondary flow controller to further assist in spreading the water along the front of the flashing. The secondary flow controller may comprise a separate component. The separate component may be attached to the flashing upstream from the remainder of the diffuser to provide initial deflection of the rain water. The secondary flow controller may alternatively comprise part of the remainder of the diffuser as opposed to being a separate component.

Guide means may be provided on the flashing to guide rain water over the flashing and towards the water diffuser. The guide means may comprise upstanding walls on the side panels of the flashing. The upstanding walls may be formed separately and attached to the flashing or may be bent up walls of the flashing edge.

In another broad form of the invention, there is provided a water diffuser adapted to catch water flowing along a roof and to more evenly spread the water along the front of the diffuser to provide more even roof drainage.

According to a further aspect of the present invention there is provided a diffuser in combination with a lateral wing or panel lapped over a wall along at least one side panel of the diffuser for construction of a penetration therethrough.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:

Figure 1. Illustrates PRIOR ART roof penetration flashing.

Figure 2. Illustrates a front view of flashing.

Figure 2A Depicts a front side of a diffuser according to a preferred embodiment of the present invention shown as being comprised of an indefinite number of repeating components.

Figure 2B Depicts a rear side of the diffuser of figure 2A according to the preferred embodiment of the present invention.

Figure 3. Illustrates the water diffuser of figures 2A and 2B attached to the front edge of the front panel of the flashing of figure 2.

Figure 4. Is a further depiction of the diffuser of figures 2A and 2B water diffuser of figure 3.

Figure 5. Illustrates a side view of the water diffuser attached to the front edge of the roof flashing and also illustrating a secondary flow controller and part of the guide means.

Figure 6. Illustrates a rear view of the water diffuser of figure 3.

Figure 7. Illustrates the water diffuser in use.

Figure 8. Illustrates a front view of the lower part of the water diffuser in use.

Figure 9. Illustrates a top view of the water diffuser with a lateral wing lapped over the side wall or guide of the diffuser.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to the figures and initially to figures 2A-8, there is illustrated a water diffuser 15, shown variously as a standalone item and also installed on a flashing for a penetration. The diffuser 15 is adapted to catch water flowing along at least one side panel 11, 12 of roof penetration flashing 14 and to more evenly spread the water along the front edge 22 (see figure 2) of the front panel 17 of the flashing to provide more even roof drainage.

Specifically, the water diffuser 15 functions to intercept the condensed water flow 13 flowing along each side panel 11, 12 of the flashing 14 (see figure 2) and to divert this flow more evenly in each of the downstream pans 1-8. Figure 2 illustrates flashing without the water diffuser and the condensed water flow 13 passing over each side panel 11,12 will predominantly flow into pans 1 -2 and 7-8 causing large amounts of water to flow in these pans with very little water flowing into pans 3-6.

Figure 3 illustrates the flashing of figure 2 with the water diffuser 15 attached. Water diffuser 15 is best illustrated in figures 2A and 2B. Diffuser 15 in the particular embodiment comprises an elongate upstanding wall 23 which extends entirely across the front edge of the front panel 17 of the flashing.

As can be seen in figures 2A and 2B, wall 23 comprises an upper vertical part 30 and a lower, forwardly and downwardly extending lower part 31. These are wall parts 30 and 31 can also be seen with the diffuser in use as shown in figure 8 and figure 3. Upper wall part 30 extends upwardly from the top of front panel 17 while lower wall part 31 contains the usual cutouts 32 to enable the lower wall part 31 to fit over the roof ridges 21 and pans of the roof sheets. Also, when the diffuser is in place, the lower wall part 31 overlies substantially the lower lip 33 (see figure 2 and figure 8) of the front panel. To ensure even water flow, the lower wall part 31 is spaced from the lower lip 33 of the flashing by a space 33a such that water can flow between the lower lip 33 of the front panel 17 and the lower part 31 of the wall 23 of the diffuser 15.

The spacing can be set to increase or decrease the water flow through the diffuser.

The wall 23 contains a plurality of spaced apart attachment means 25 which, in the particular embodiment, comprises bent out metal tab members 26. Each tab member 26 is formed with an opening to enable a screw fastener 34 (see for instance figure 6) to fasten the diffuser to the edge of the front panel 17 of the flashing. Figure 5 partially illustrates an additional feature which comprises an additional panel 24 (shown in outline only) which can function to prevent water jumping over the diffuser front wall.

The attachment means 25 are spaced apart by a distance which is the same as the spacing between the roof sheet ridges 21 (see for instance figure 6). One advantage of this is that it ensures that the screw fastener 34 passes through a ridge of a roof sheet which is required as opposed to passing through the pan portion which is not allowed.

On each side of a tab member is a bracket member 27 comprising a pair of spaced apart substantially triangular brackets. These can function to provide rigidity to the diffuser to prevent deformation caused by the weight of water pressing against the wall 23.

Referring to figure 6, it can be seen that tab member 26 prevents or substantially reduces the ability of water flowing through the diffuser to flow directly onto the roof ridge 21. Instead, tab member 26 assists in guiding the water into each of the downstream pans (20 in figure 6) which is desirable. A secondary flow controller 28 (see figure 5) is provided on the juncture of the front panel 17 and side panel 12 (and 11) and is spaced upstream from wall 23. The secondary flow controller, in the preferred embodiment, comprises a separate component having an upper wall portion 35 to initially intercept a portion of the water (see figure 7) flowing over panel 11 or 12 and to divert this water more towards a middle portion of diffuser 15. Controller 28 is formed with a lower opening 36 to allow a portion of the water to flow directly to the part of diffuser 15 immediately downstream from the controller. Controller 28 therefore functions to "split" the water flow into a lower portion that can flow through opening 36 and against the diffuser, and an upper portion wall portion 35 that is deflected more towards a central part of the diffuser. Another function of controller 28 is to slow the velocity of water passing over panel 11 or 12 which may otherwise strike an edge portion of the diffuser with sufficient force to leap over the upstanding wall part 23 of the diffuser - which would be undesirable. A secondary flow controller 28 may be provided on each side panel 11,12 and may be particularly suited for larger flow volumes along the side panels 11,12.

Figure 7 and figure 8 illustrate the diffuser in use. Referring particularly to figure 7, it can be seen that as water flows over side panel 11, part of the water is intersected by the secondary flow controller 28 and diverted more to the center of the diffuser. The water flows more evenly behind diffuser 15 and over front panel 17. The diffuser allows the water to pass more evenly into each of the downstream pans 1-8 (only pans 1-5 illustrated in figure 7). Figure 8 particularly illustrates pans 3-5 and shows how the diffuser 15 diverts water flow into these pans which would otherwise receive very little water flow.

Referring again to figure 7, a guide means 29 in the form of an upstanding wall or lip is provided at the edge of each side panel 11,12 and this functions to keep water on the side panel prevents this condensed water flow into an adjacent pan (see for instance pan 37 in figure 3) which can cause uneven water flow along the roof sheets. The wall 29 also adds structural integrity to the diffuser. Furthermore, as shown in Figure 9, a lateral sheet or wing 39 may be provided in combination with the diffuser which has an edge lapped over the side wall 29 of the diffuser. The lateral wing may be used as a base for constructing further penetrations through the roof as desired.

USE FOR THE INVENTION

The above description identifies at least one specific, substantial and credible use for the invention. Specifically the diffuser demonstrates that it is now possible to maintain even water flow about a flashed off penetration thereby reducing the possibility of gutter overflow and roof leakage.

In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. The term “comprises” and its variations, such as “comprising” and “comprised of is used throughout in an inclusive sense and not to the exclusion of any additional features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art.

Throughout the specification and claims (if present), unless the context requires otherwise, the term "substantially" or "about" will be understood to not be limited to the value for the range qualified by the terms.

Any embodiment of the invention is meant to be illustrative only and is not meant to be limiting to the invention. Therefore, it should be appreciated that various other changes and modifications can be made to any embodiment described without departing from the spirit and scope of the invention.

Claims (17)

1. The claims defining the invention are as follows:

   1. A water diffuser adapted to catch water flowing along at least one side of roof penetration flashing and arranged to spread water flowing along the along the front of the flashing to facilitate even roof drainage wherein the diffuser comprises an elongate upstanding wall, a positioning arrangement to removably position said upstanding wall across the front of the flashing to catch the water flowing along at least one side of the roof penetration flashing, wherein at least part of said wall is spaced apart from the flashing such that water can flow therebetween.
2. 2. The diffuser as claimed in claim 1, wherein the upstanding wall comprises an upper part and a lower part, the upper, in use, extending upwardly from the flashing and the lower part, in use, containing cutouts to corresponding to ridges and pans of the roof sheets.
3. 3. The diffuser as claimed in claim 2, wherein the lower part is spaced from the flashing.
4. 4. The diffuser as claimed in any one of the preceding claims, including at least one attachment means for attaching the diffuser in a desired location.
5. 5. The diffuser as claimed in claim 4, wherein a plurality of attachment means are provided which are spaced apart.
6. 6. The diffuser as claimed in claim 4 or claim 5, wherein the attachment means comprises a tab member adapted to overlie the flashing and adapted to be fastened to the flashing.
7. 7. The diffuser as claimed in claim 6 comprising a plurality of spaced apart attachment means each comprising a tab member, the tab members adapted to overlie a roof sheet ridge.
8. 8. The diffuser as claimed in claim 6 or 7, wherein the attachment means includes an upstanding bracket member adjacent one side of the tab member.
9. 9. The diffuser as claimed in claim 8, including a bracket member adjacent each side of the tab member.
10. 10. The diffuser as claimed in any one of the preceding claims including a secondary flow controller.
11. 11. The diffuser as claimed in claim 10, wherein the secondary flow controller comprises a separate member spaced upstream from the fluid flow and adapted to divert part of the fluid flow to a more central part of the diffuser.
12. 12. The diffuser as claimed in any one of the preceding claims including a water guide means.
13. 13. The diffuser as claimed in claim 12, wherein the guide means comprises an upstanding wall on a side panel of the flashing.
14. 14. Roof flashing comprising an upstanding collar, rear panel, a front panel with a front edge, side panels, and a diffuser as claimed in any one of claims 2-14, the upstanding wall being adjacent the front edge of the front panel.
15. 15. Roof flashing as claimed in claim 14, including a secondary flow controller as claimed in claim 11, the controller being positioned at least partially on a side panel of the flashing.
16. 16. Roof flashing as claimed in claim 14 or claim 15, including a water guide means as claimed in claim 12 or claim 13, the water guide means comprising an upstanding wall on each side panel.
17. 17. A roof flashing as claimed in any one of claims 15 to 17 in combination with a lateral wing lapped over a wall along of at least one side panel for construction of a penetration therethrough. *****************