AU2021232683A1 - Fire resistant roof drainage vent assembly and method of installing same - Google Patents

Abstract

The present invention relates to a drainage vent assembly of the type that is adapted to draw exhaust gas from (or provide intake gas to) a building drainage system. The vent assembly of the present invention is particularly useful in bushfire prone regions since the vent assembly substantially prevents heat conduction from a pipe disposed above a roofline to pre-existing pipework below the roofline. The present invention further relates to a method of installing the vent assembly. 44 40 42 160 -- --- 20 46 36 328 34 22

Description

40

42

160

-- - - 20

46

36

34 328

FIRE RESISTANT ROOF DRAINAGE VENT ASSEMBLY AND METHOD OF INSTALLING SAME FIELD OF THE INVENTION

[0001] The present invention relates to a drainage vent assembly of the type that is adapted to draw exhaust gas from (or provide intake gas to) a building drainage system. The vent assembly of the present invention is particularly useful in bushfire prone regions since the vent assembly substantially prevents heat conduction from a pipe disposed above a roofline to pre-existing pipework below the roofline. The present invention further relates to a method of installing the vent assembly.

BACKGROUND OF THE INVENTION

[0002] Drainage vents of the type that include a vertical pipe section extending from below a roofline (where the vent pipe is connected to a below roofline fitting) to a location above the roofline, perform a number of important functions. For example, in addition to venting gases from a sewerage or similar drain system, and allowing same to dissipate above the roofline, such vents also function to allow the material flowing through the drain system to flow freely. This is achieved by allowing air to flow into the system and equalize pressure within the associated pipes. In other words, drainage vents extending above a roofline not only vent fumes out of a sewerage, or similar drain system, but also facilitate the intake of air into such systems for the purpose of maintaining a neutral air pressure.

[0003] Some buildings are located in bushfire prone regions, and there are regulatory requirements that provide building safeguards including in relation to building materials and configurations available for use in those regions. For example, Bushfire Attack Level (BAL) rating requirements provide that vent assemblies including an exposed portion of pipe require apertures for entry/exit of gas that do not exceed 3mm diameter in order to prevent, or at least substantially reduce, the risk of ember attack. Polyvinyl Chloride (PVC), which is not fire resistant, is commonly used above the roofline for drainage vents, even in bushfire prone regions. However, BAL ratings provide that materials above a roofline should be fire resistant.

[0004] Some tradespeople attempt to comply with the BAL ratings by using fire resistant material in the exposed sections of the drainage vent, such as a suitable metal. However, using fire resistant material only in the exposed sections of the vent does not address the problem of heat conduction to the below roofline pipework. PVC is typically used in the below roofline pipework since it represents the preferred, most commonly available and cost-effective material.

[0005] Therefore, existing drainage vent configurations may cause damage to materials below the roofline as a result of conduction of heat, due to materials that are not fire resistant being used above the roofline, or due to combustible materials below the roofline being in direct contact with materials (fire resistant or otherwise) above the roofline. The Applicant is not aware of any vent product that addresses the abovementioned problems whilst complying with BAL ratings.

[0006] Accordingly, there is a need for vent systems to be constructed and/or assembled in a manner that avoids thermal conduction, or at least provides sufficient thermal insulation, between the above roofline fire resistant vent pipe and the below roofline pipework. The below roofline pipework will typically include a vertically extending pipe that terminates at a pipe end, the pipe end providing a point of attachment for a vent assembly that extends above the roofline.

[0007] In addition to avoiding thermal conduction between the above roofline and below roofline components, there is also a need to ensure that the installation of such systems by tradespeople is efficient and that the integrity of the connection (and hence support for the upstanding vent assembly) is not compromised. In this regard, it is beneficial for the installation process to be achieved solely from a position above the roofline (where the below roofline pipework is already completed), i.e. without requiring the tradesperson to enter an area below the roofline (e.g. inside the roof space) for the purpose of installing any vent components. Reducing the travel and requirement to carry components from one location to another significantly reduces the time, effort and cost associated with installing such components.

[0008] It is an object of the present invention to overcome or at least ameliorate some of the aforementioned problems, or to provide the public with one or more useful alternatives.

[0009] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any suggestion, that the prior art forms part of the common general knowledge.

SUMMARY OF THE INVENTION

[0010] In a first aspect, the present invention provides a drainage vent assembly for installation to pre-existing pipework of a drainage system, the pre-existing pipework extending substantially to a roofline for exhausting gas from the drainage system, the drainage vent assembly including: a pipe of fire resistant material having a first end that is upwardly disposed when the assembly is installed, and a second end distal from the first end; and a connecting member associated with the second end of the pipe that is distal from the first end, the connecting member engaging the second end of the pipe and dimensionally configured to attach to the pre-existing pipework, and

at least one spacer preventing direct contact between the connecting member and the pipes second end.

[0011] Connection between the pipe and the connecting member is configured such that thermal conduction from the pipe to the connecting member, and hence to the pre-existing pipework, is substantially avoided, or reduced, by use of the at least one spacer.

[0012] In an embodiment, the at least one spacer is positioned between overlapping walls associated with the second end of the pipe and the connecting member thereby causing the overlapping walls to be separated radially from one another.

[0013] In an embodiment, the connecting member includes an internal annular shoulder, and the at least one spacer is positioned between the internal annular shoulder and the second end of the pipe thereby causing the second end of the pipe to be separated longitudinally from the internal annular shoulder.

[0014] In an embodiment, the pipe has a circular cross section and defines a first hollow passage through which gas passes, and the connecting member is in the form of a receptacle of circular cross section that engages the second end of the pipe and further includes a male pipe section that defines a second hollow passage in fluid communication with the first hollow passage.

[0015] In this embodiment, the pre-existing pipework includes a female pipe end of circular cross section configured to receive and thereby retain the male pipe section of the receptacle which is dimensionally configured for insertion into the female pipe end.

[0016] In this embodiment, the receptacle engages the second end of the pipe by further including a female pipe section having a cross sectional dimension for receiving the pipe's second end.

[0017] In this embodiment, the female pipe section includes a stepped cross-sectional diameter as compared with the male pipe section thereby defining the internal annular shoulder.

[0018] In this embodiment, the at least one spacer includes first and second annular sealing members located between overlapping walls associated with the second end of the pipe and receptacle, the first annular sealing member maintaining a longitudinal distance between the second end of the pipe and the internal annular shoulder, and a radial distance between the overlapping walls, and the second annular sealing member also maintaining a radial distance between the overlapping walls at a longitudinally spaced apart location from the first annular sealing member.

[0019] In this embodiment, the first annular sealing member includes a uniform outer diameter that substantially corresponds with an internal diameter of the receptacle female pipe section such that the first annular sealing member is capable of location in the female pipe section of the receptacle adjacent the annular shoulder.

[0020] In this embodiment, the first annular sealing member includes a non-uniform internal diameter such that the first annular sealing member includes a flanged base portion that extends radially inwardly, and an upper non-flanged portion, the flanged base portion having a smaller internal diameter as compared with the upper non-flanged portion and thereby defining an annular shelf upon which the distal end of the pipe sits such that the annular shelf maintains the longitudinal distance between the distal point of the second end of the pipe and the internal annular shoulder whilst the upper non-flanged annular portion maintains the radial distance between the second end of the pipe and the female pipe section of the receptacle.

[0021] In this embodiment, the second annular sealing member includes a uniform internal diameter of a dimension that substantially corresponds with an outer wall diameter of the second end of the pipe.

[0022] In this embodiment, the outer diameter of the second annular sealing member is non-uniform such that the second annular sealing member includes a flanged upper portion that extends radially outwardly, and a lower non-flanged portion, the flanged upper portion having a greater external diameter as compared with the lower non-flanged portion and thereby creating a lip over an upper most edge of the receptacle female pipe section, wherein an outer edge of the flanged upper portion sits flush with the outer wall of the female pipe section.

[0023] In this embodiment, a hollow annular space exists between an outer wall of the pipe's second end and an inner wall of the receptacle female pipe section between the longitudinally spaced apart first and second annular sealing members, and a thickness of the non-flanged upper portion of the first annular sealing member substantially corresponds with a thickness of the non-flanged lower portion of the second annular sealing member, thereby causing the annular hollow space to be substantially uniform along its longitudinal length.

[0024] In this embodiment, the hollow annular space is filled with a non-conductive adhesive to create a thermally insulating adhesion between the fire resistant pipe and the receptacle female pipe section.

[0025] In this embodiment, the non-conductive adhesive is silicon adhesive.

[0026] In an alternative embodiment, the connecting member is in the form of a collar having a circular cross section that engages the second end of the pipe.

[0027] In this embodiment, the pre-existing pipework includes a pipe end and the collar is configured to threadably engage the pipe end.

[0028] In this embodiment, the collar engages the second end of the pipe by further including a female pipe section having a cross-sectional dimension for receiving the pipe's second end.

[0029] In this embodiment, the at least one spacer includes first and second annular sealing members located between overlapping walls associated with the second end of the pipe and collar, the first annular sealing member maintaining a longitudinal distance between the second end of the pipe and the internal annular shoulder, and a radial distance between the overlapping walls, and the second annular sealing member also maintaining a radial distance between the overlapping walls at a longitudinally spaced apart location from the first annular sealing member.

[0030] In this embodiment, the first annular sealing member includes a uniform outer diameter that substantially corresponds with an internal diameter of the collar female pipe section such that the first annular sealing member is capable of location in the female pipe section of the collar adjacent the annular shoulder.

[0031] In this embodiment, the first annular sealing member includes a non-uniform internal diameter such that the first annular sealing member includes a flanged base portion that extends radially inwardly, and an upper non-flanged portion, the flanged base portion having a smaller internal diameter as compared with the upper non-flanged portion and thereby defining an annular shelf upon which the digital point of the second end of the pipe sits such that the annular shelf maintains the longitudinal distance between the distal point of the second end of the pipe and the internal annular shoulder whilst the upper non-flanged annular portion maintains the radial distance between the second end of the pipe and the female pipe section of the collar.

[0032] In this embodiment, the second annular sealing member includes a uniform internal diameter of a dimension that substantially corresponds with an outer wall diameter of the second end of the pipe.

[0033] In this embodiment, the outer diameter of the second annular sealing member is non-uniform such that the second annular sealing member includes a flanged upper portion that extends radially outwardly, and a lower non-flanged portion, the flanged upper portion having a greater external diameter as compared with the lower non-flanged portion and thereby creating a lip over an upper most edge of the collar female pipe section, wherein an outer edge of the flanged upper portion sits flush with the outer wall of the female pipe section.

[0034] In this embodiment, a hollow annular space exists between an outer wall of the pipe's second end and an inner wall of the collar female pipe section between the longitudinally spaced apart first and second annular sealing members, and a thickness of the non-flanged upper portion of the first annular sealing member substantially corresponds with a thickness of the non-flanged lower portion of the second annular sealing member, thereby causing the annular hollow space to be substantially uniform along its longitudinal length.

[0035] In this embodiment, the hollow annular space is filled with a non-conductive adhesive to create a thermally insulating adhesion between the fire resistant pipe and the collar female pipe section.

[0036] In this embodiment, the non-conductive adhesive is silicon adhesive.

[0037] In an embodiment, the at least one spacer is silicone rubber. It is to be understood that the at least one spacer may be any material that has properties similar to silicone rubber, i.e. any material that is relatively non-heat conductive.

[0038] In an embodiment, the first end of the assembly that is upwardly disposed when installed includes a grating having a plurality of apertures that enable entry/exit of gas. In a particular embodiment, each of the plurality of apertures are smaller than 3mm in diameter.

[0039] In an embodiment, the grating includes a cap at its uppermost end which is non apertured to prevent or at least minimize rain entry.

[0040] In an embodiment, the fire resistant pipe and associated grating is constructed of metal or other suitable fire resistant material.

[0041] In an embodiment, the vent assembly is installed with flashing at a junction between the roofline and the pipe, the flashing located above the roofline. In an embodiment, the flashing is also made of metal, or other fire resistant material such as silicone rubber. In a particular embodiment, the existing pipework extends through the roofline and once the drainage vent assembly is firmly attached to the existing pipework, the fire resistant flashing protects the existing pipework from exposure to unsafe temperatures. However, more commonly, the existing pipework will terminate at a location below the roofline thereby requiring an installer to create access through the roof to attach the drainage vent assembly connecting member to the existing pipework. By terminating below the roofline, the lower end of the assembly (i.e. the elements below the second annular sealing member) will also be located substantially beneath the roofline once installed, which prevents or at least minimizes heat damage to these elements.

[0042] In a second aspect, the present invention provides a drainage venting system including existing pipework extending substantially to a roofline for exhausting gas from the drainage system, and a drainage vent assembly as defined in one or more of the preceding statements.

[0043] In a third aspect, the present invention provides a method of installing a drainage vent assembly according to any one or more of the preceding statements, the method including: locating the pre-existing pipework; and from a location above the roofline, attaching the connecting member to a pipe end associated with the pre-existing pipework such that the installed drainage vent assembly, or part thereof, is disposed above the roofline subsequent to installation.

[0044] In a fourth aspect, the present invention provides a method of manufacturing a drainage vent assembly according to any one of the preceding statements in which the connecting member is defined as a receptacle, the method including:

inserting the first annular sealing member into the receptacle female pipe section until the flanged base portion thereof abuts with the internal annular shoulder; inserting the pipe until the second end abuts with the flanged base portion to temporarily retain the pipe's second end such that said longitudinal and radial distances are maintained, subsequently applying the non-conductive adhesive to the hollow annual space between the outer wall of the pipe distal end and the inner wall of the receptacle female pipe section, subsequently causing the second annular sealing member to engage the upper most edge of the receptacle female pipe section, and wherein, upon curing of the non-conductive adhesive, the pipe is secured in a position in which no direct contact occurs with the receptacle.

[0045] In a fifth aspect, the present invention provides a method of manufacturing a drainage vent assembly according to any one of the preceding statements in which the connecting member is defined as a collar, the method including:

inserting the first annular sealing member into the collar female pipe section until the flanged base portion thereof abuts with the internal annular shoulder; inserting the pipe until the pipe second end abuts with the flanged base portion to temporarily retain the second end such that said longitudinal and radial distances are maintained, subsequently applying the non-conductive adhesive to the hollow annular space between the outer wall of the pipe distal end and the inner wall of the collar female pipe section, subsequently causing the second annular sealing member to engage at the upper most edge of the collar female pipe section, and wherein, upon curing of the non-conductive adhesive, the pipe is secured in a position in which no direct contact occurs with the collar.

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Features of the present disclosure are illustrated by way of example and not limited in the following figure(s), in which like numerals indicate like elements, in which:

[0047] Figure 1 illustrates an exploded, perspective view of a fire resistant drainage vent assembly including a pipe and receptacle according to an embodiment of the present invention.

[0048] Figure 2 illustrates an enlarged perspective view of the fire resistant drainage vent assembly of Figure 1, assembled with below roofline pre-existing pipework.

[0049] Figure 3 illustrates an enlarged exploded perspective view of a connecting region between a pipe and the receptacle associated with the fire resistant drainage vent assembly of Figure 1.

[0050] Figure 4a illustrates an enlarged cross-sectional view of the connecting region of the assembly of Figure 1 in an assembled state.

[0051] Figure 4b illustrates an enlarged cross-sectional view of the connecting region of a fire resistant drainage vent assembly including a pipe and collar according to an alternative embodiment to that which is shown in Figure 4a.

DETAILED DESCRIPTION OF THE EMBODIMENT(S) OF THE INVENTION

[0052] For simplicity and illustrative purposes, the present disclosure is described by referring to an exemplary embodiment thereof. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. It will be readily apparent however, that the present disclosure may be practiced without limitation to these specific details. In other instances, some methods and structures have not been described in detail in order to avoid unnecessarily obscuring the present disclosure.

[0053] As used herein, the terms "a" and "an" are intended to denote at least one of a particular element, the term "includes" means includes but not limited to, the term "including" means including but not limited to, and the term "based on" means based at least in part on.

[0054] The present invention relates to a drainage vent assembly (10) configured to be attached to existing pipework that extends up to a roofline (12). The existing pipework may be associated with a drain system, such as a sewerage system associated with a building, of the type which requires a vent assembly extending above the roofline to vent sewerage gases and allow same to dissipate above the roofline (12), and which may also function to draw air into such systems for the purpose of maintaining a neutral air pressure.

[0055] In the embodiments shown, and in what is the most effective embodiment in bushfire prone areas where the area above the roofline (12) may be exposed to extreme heat, the existing pipework (50) extends to a position below the roofline and thereby allows for certain components of the drainage vent assembly (10) to also be positioned below the roofline (12), as described in greater detail below. However, there may be scenarios in which the existing pipework terminates at the roofline (12) or just above the roofline (12), and reference herein to pre-existing pipework extending "substantially to a roofline" is intended to include within its scope any one of these three scenarios.

[0056] According to the embodiment depicted in Figure 1, the drainage vent assembly (10) is configured to extend substantially vertically through and above the roofline (12) when installed, and includes at an upwardly disposed end, a first end of a pipe (14) comprising a fire resistant material to ensure that the vent assembly (10) can be utilised in bushfire prone regions. The pipe (14) includes a second end (20) distal from the first end and defines a first hollow passage (16) through which gas may pass. The vent assembly (10) further includes, at the end of the assembly distal from the upwardly disposed end, a connecting member (18) that is assembled with the second end of the pipe (14) in a manner that avoids thermal conduction, as described in greater detail below. In the embodiments shown in Figures 1-3 and 4a, the connecting member (18) is a receptacle (18a) having an upper end (24a) (also referred to herein as a female pipe section) that engages the distal end (20) of the pipe, and a lower end (25a) configured to attach the vent assembly (10) to pre-existing below roofline pipework (50) associated with the drain system. However, a connecting member other than a receptacle could be used, provided it performs a similar function as the receptacle described herein. For example, in the embodiment shown in Figure 4b, the connecting member is a collar (18b) having an upper end (24b) (also referred to herein as a female pipe section) that engages the distal end (20) of the pipe, and a lower end (25b) configured to attach the vent assembly (10) to the pre-existing below roofline pipework (50).

[0057] According to the embodiment in which the connecting member is a receptacle (18a), pre-existing drain system pipework (50) includes a female pipe end, and the receptacle (18a) includes a correspondingly shaped male end (25a) dimensionally configured to attach to the female pipe end (50) using an appropriate adhesive, as shown in Figures 2 and 4a. The female pipe end (50) may be accessed from a location above the roofline (12) by, for example, removing a roof tile or cutting a section out of a corrugated iron sheet (not detailed in the Figures). The female pipe end (50) is thereby exposed below the roofline, and is configured to engage and thereby retain a lower end (25a) of the receptacle (18a). The receptacle (18a) includes a second hollow passage (22) through which gas may pass, which is in fluid communication with the first hollow passage defined by the pipe (14) when assembled.

[0058] According to the embodiment in which the connecting member is a collar (18b), pre-existing drain system pipework (50) may include a threaded end (52), which in the embodiment shown is a male thread, and the collar (18b) may include a female threaded end (25b) dimensionally configured to engage the threaded pipe end (52) of pipework (50), as shown in Figure 4b. In an alternative embodiment (not shown), the pipework (50) could include a female threaded end, and in this embodiment the collar (18a) would include a correspondingly shaped male threaded end.

[0059] It will become apparent that engagement between a distal end (20) of the pipe (14) and the receptacle/collar (18a/18b) during assembly of the vent assembly (10) involves the distal end (20) of the pipe (14) engaging with the upper end (24a/24b) of the receptacle/collar (18a/18b), wherein the engaging ends are separated by a distance. According to an embodiment, a radial distance (26) as well as a longitudinal distance (27) is established. It will be further appreciated that the distance (26, 27) between the components, which ensures that there is no direct contact between the fire resistant pipe (14) and the potentially combustible receptacle/collar (18a/18b) is maintained by at least one spacer, e.g. annular sealing members (also referred to as seals) (28, 29).

[0060] By ensuring that the pipe (14) of the vent assembly (10) which extends through and above the roofline (12) is fire resistant, with no direct contact and sufficient thermal insulation between the pipe (14) and receptacle/collar (18a/18b), the conduction of heat from the pipe (14) to the receptacle/collar (18a/18b) is avoided, or at least reduced to a safe level. Hence, by utilising the vent assembly (10) of the present invention, there is reduced likelihood that the below roofline components, including the pipework (50), will be subject to heat at a level that may cause the pipework (50) to deform or combust and present a fire hazard below the roofline (12). These particular arrangements according to embodiments of the present invention further enable a tradesperson to effect installation solely from the rooftop of a building.

[0061] It is to be understood that reference to a "building" herein is intended to include within its scope homes or any other residential or commercial building having a drainage system that requires venting.

[0062] In the embodiment depicted in Figures 1-3 and 4a in which the connecting member is a receptacle (18a), the pipe (14) and receptacle (18a) are both of circular cross-section, and the receptacle (18) includes a "stepped up" diameter towards its upper end which defines an internal annular shoulder (30a). In other words, the internal diameter of the receptacle (18a), at its upper end (24a) between the shoulder (30a) and an uppermost edge thereof is greater than the diameter of the lower receptacle end (25a) at a location below the shoulder (30a). In the embodiment depicted in Figure 4b in which the connecting member is a collar (18b), the pipe (14) and collar (18b) are both of circular cross-section, and the collar (18b) also includes an internal annular shoulder (30b) that projects radially inwardly at a location between the upper end (24b) and the female threaded end (25b).

[0063] The use of at least one spacer retains the above roofline vent pipe (14) in position in the receptacle/collar (18a/18b) during assembly of the vent assembly (10) and creates a sufficient distance to prevent, or at least sufficiently reduce, thermal conduction between the two engaging ends (20) and (24a/24b) during use. In the embodiment shown, there is a radial distance (26) and a longitudinal distance (27) created by a first spacer which is in the form of an annular silicone rubber sealing member (28). The radial space (26) is filled with silicone rubber adhesive. The vent assembly (10) may include more than one spacer and, in the embodiments shown, the assembly (10) includes a second annular silicone rubber seal (27). However, it is to be understood that an alternate number of spacers, or spacers that are dimensioned or arranged in any other way may also be suitable. For example, the spacers need not necessarily be annular in shape.

[0064] It is to be further understood that whilst most pipe sections used in plumbing applications are of circular cross section, the present invention is not intended to be limited to the use of circular cross section pipework. If pipework of an alternate cross section is used, then the skilled addressee would appreciate that some associated components such as the spacers for example may also need to be shaped accordingly.

[0065] In the particular embodiments shown, the first (28) and second (29) annular silicone rubber seals are longitudinally spaced apart (noting that the longitudinal axis (54) relates to the length of the pipe (14) and receptacle (18) and extends transversely or obliquely to an axis associated with the roofline (12)) such that the first annular silicone rubber seal (28) maintains a radial distance between an outer wall of the lower most end (20) of the pipe (14) and the inner wall of the upper most end (24a/24b) of the receptacle/collar (18a/18b). In addition to maintaining a radial distance, a longitudinal distance is also maintained between the lower most end (20) of the pipe (14) and the internal shoulder (30a/30b) of the receptacle/collar (18a/18b). This is achieved by the particular configuration of the first annular rubber seal (28) as described in greater detail below.

[0066] The first annular silicone rubber seal (28) includes a uniform outer diameter such that the first silicone rubber seal (28) is capable of location in the upper end of the receptacle/collar (18a/18b) above the annular shoulder (30a/30b) but not below the annular shoulder (30a/30b) in view of the reduced dimension in that region. In particular, the outer diameter of the first annular silicone rubber seal (28) substantially corresponds with an internal diameter of the upper end (24a/24b) of the receptacle/collar (18a/18b), i.e. between the shoulder (30a/30b) and an upper most edge thereof. In this way, the first annular silicone rubber seal (28) may be inserted until it abuts with the internal shoulder (30a/30b), at which location the first annular silicone rubber seal (28) is positioned to receive and secure the lower end (20) of the pipe (14) during assembly.

[0067] In this regard, the first annular silicone rubber seal (28) may include a non-uniform internal diameter such that the seal (28) includes a flanged base section (32) having a smaller internal diameter as compared with an upper non-flanged section (34). Since an internal diameter associated with the non-flanged section (34) substantially corresponds with an outer diameter of the distal end (20) of the pipe (14), the pipe (14) may be inserted into the receptacle/collar (18a/18b) and received inside the non-flanged section (34) of the first annular silicone rubber seal (28) which acts to retain the pipe distal end (20) during assembly, whilst ensuring that said distances (26, 27) are maintained between the pipe distal end (20) and each of the receptacle/collar upper end (24a/24b) and shoulder (30a/30b) respectively.

[0068] Accordingly, the internal shoulder (30a/30b) and the first annular silicone rubber seal (28) nestled therein create an annular "shelf' upon which the lowermost edge of the pipe (14) sits whilst the flanged annular lower portion maintains a longitudinal distance (27) between the distal end of the pipe and the internal annular shoulder (30a/30b) of the receptacle/collar (18a/18b) and the non-flanged upper portion maintains a radial distance (26) between the distal end of the pipe (14) and a portion of the upper end of the receptacle/collar (18a/18b) adjacent the shoulder (30a/30b).

[0069] The skilled addressee will appreciate that depending upon the length of the distal end (20) of the pipe (14) inserted into the receptacle/collar (18a/18b), additional spacers may be required. In the embodiments shown, for example, a second annular silicone rubber seal (29) is used in order to provide additional means of ensuring separation between the outer diameter of the pipe (14) and the upper end (24a/24b) of the receptacle/collar (18a/18b). In this regard, the second annular silicone rubber seal (29) includes a uniform internal diameter of a dimension that substantially corresponds with an outer diameter of the pipe (14). Since the second annular silicone rubber seal (29) is positioned at the top of the upper end (24a/24b) of the receptacle/collar (18a/18b), it may include a non-uniform outer diameter to enable the seal (29) to engage the upper end of the receptacle/collar (18a/18b).

[0070] In particular, the second annular silicone rubber seal (29) may include a flanged upper section (36) that extends radially outwardly, the flanged upper section (36) having a greater external diameter as compared with the external diameter of a lower non flanged section (38) thereof. The skilled addressee will appreciate that the flanged upper section (36) acts as a cap since an external diameter associated with the non-flanged section (38) substantially corresponds with an internal diameter of the receptacle/collar upper end (24a/24b), and the second annular silicone rubber seal (29) may be slid down over the pipe (14) until the upper flanged section (36) abuts with the upper most edge of the receptacle/collar (18a/18b), at which location the second annular silicone rubber seal (29) sits to assist in maintaining the radial distance (26) between the outer wall of the vertical pipe section (14) and the upper end (24a/24b) of the receptacle/collar (18a/18b).

[0071] Silicone rubber adhesive ora similar non-heat conductive adhesive maybe used to fill annular space (26), with the second annular silicone rubber seal (29) capping the adhesive-filled hollow space (26). The silicone rubber adhesive acts to create adhesion and maintain radial separation of the receptacle/collar upper end (24a/24b) and the distal end (20) of the pipe (14) whilst also acting as thermal insulation.

[0072] In the embodiment in which the connecting member is a receptacle (18a), a skilled tradesperson can then install the drainage vent assembly (10) by applying a solvent cement PVC glue, or similar, to an external surface associated with the male end (25a) of the receptacle (18a) as well as to a corresponding internal surface associated with the female pipe end of the pre-existing pipework (50), and inserting the male end of the receptacle (18a) into the female pipe end of pipework (50) so that they snuggly engage and adhere to each other once the glue is cured. In the embodiment in which the connecting member is a collar (18b), a tradesperson can install the vent assembly (10) by screwing the collar (18b) onto the female pipe end of pipework (50). In both embodiments, this may all be achieved from a location above the roofline (12) without the need for the tradesperson to enter a location below the roofline (12). The drainage vent assembly (10) is thus secured in a substantially vertical orientation through and above the roofline (12).

[0073] The drainage vent assembly (10) maybe assembled/manufactured according to the following steps:

(a) inserting the first annular sealing member (28) into the receptacle/collar female pipe section (24a/24b) until the flanged base portion (32) thereof abuts with the internal annular shoulder (30a/30b);

(b) inserting the pipe (14) until the pipe distal end (20) abuts with the flanged base portion (32) to temporarily retain the pipe distal end (20) such that said longitudinal (27) and radial (26) distances are maintained,

(c) subsequently applying the non-conductive adhesive to the hollow annular space (26) between the outer wall of the pipe distal end (20) and the inner wall of the receptacle/collar female pipe section (24a/24b),

(d) subsequently causing the second annular sealing member (29) to engage at the upper most edge of the receptacle/collar female pipe section (24a/24b), and

(e) wherein, upon curing of the non-conductive adhesive, the pipe (14) is secured in a position in which no direct contact occurs with the receptacle/collar (18a/18b).

[0074] According to a particular embodiment, the receptacle/collar (18a/18b) are made of PVC, and the adhesive used to connect the male end (25a) of the receptacle (18a) and the female pipe end of pipework (50) is a solvent cement PVC glue. However, it is to be understood that other adhesives may be used and selection of same will depend upon the choice of material used in manufacture of the receptacle/collar (18a) and/or below roofline pipework (50). Given that these components/adhesives are made of PVC material, they are susceptible to heat damage, and the skilled addressee will appreciate that locating these components below the roofline (12) will prevent or at least minimise heat damage.

[0075] Figures 1 and 2 also depict a grating (40) having a plurality of apertures (42) that enable entry/exit of gas. In a particular embodiment, each of the plurality of apertures (42) will be less than 3mm in diameter in order to comply with the Australian BAL rating, which is intended to prevent, or at least substantially reduce, ember attack during bushfires. The grating (40) extends upwardly from an upper end of the vertical pipe section (14) and includes an end cap (44). Whilst other configurations may be suitable, the grating (40) is attached to the upper end of the vertical pipe section (14) by having a smaller diameter cross-section which enables the grating (40) to be press fitted into the upper end of the vertical pipe section (14). The grating cap (44) at its uppermost end is non-apertured to prevent or at least minimize rain entry.

[0076] Figure 1 also depicts an appropriate flashing (46) at the junction between the roofline (12) and anywhere along the lower edge of the vertical pipe section (14). In the case of a metal (e.g. corrugated iron) roof, the flashing (46) may be a substantially frusto conical shaped member as shown in Figure 1 that is configured to sit above the roof and not only obscure the junction from sight but also seal the roofline aperture created by the drainage vent assembly insertion through the roofline (12). In this regard, the flashing may also be constructed of a fire resistant material, most commonly, silicon rubber. The flashing shown is by example only, and may be configured differently depending on the roof type. For example, in the case of a tiled roof, the flashing may be a conical shaped silicon rubber flashing which sits above an appropriate mount (not shown).

[0077] The skilled reader will appreciate that the drainage vent assembly and method of installing same as described and defined herein may embody a range of benefits and advantages including thermal insulation between a fire resistant portion of a drainage vent assembly that, once installed, may be subject to high temperatures, and a connector attached to the fire resistant portion that is protected against those potentially high temperatures.

[0078] Throughout this specification and claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to mean the inclusion of a stated feature or step, or group of features or steps, but not the exclusion of any other feature or step, or group of features or steps.

[0079] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any suggestion that the prior art forms part of the common general knowledge.

Claims (40)

The claims defining the invention are as follows:

1. A drainage vent assembly for installation to pre-existing pipework of a drainage system, the pre-existing pipework extending substantially to a roofline for exhausting gas from the drainage system, the drainage vent assembly including: a pipe of fire resistant material having a first end that is upwardly disposed when the assembly is installed, and a second end distal from the first end; a connecting member associated with the second end of the pipe that is distal from the first end, the connecting member engaging the second end of the pipe and being dimensionally configured to attach to the pre-existing pipework, and at least one spacer preventing direct contact between the connecting member and the pipe's second end.

2. A drainage vent assembly according to claim 1, wherein thermal conduction from the pipe to the connecting member, and hence to the pre-existing pipework, is substantially avoided by use of the at least one spacer.

3. A drainage vent assembly according to either claim 1 or claim 2, wherein the at least one spacer is positioned between overlapping walls associated with the second end of the pipe and the connecting member thereby causing the overlapping walls to be separated radially from one another.

4. A drainage vent assembly according to any one of the preceding claims, wherein the connecting member includes an internal annular shoulder, and the at least one spacer is positioned between the internal annular shoulder and the second end of the pipe to cause the second end of the pipe to be separated longitudinally from the internal annular shoulder.

5. A drainage vent assembly according to claim 4, wherein the pipe has a circular cross section and defines a first hollow passage through which gas passes, and the connecting member is in the form of a receptacle of circular cross section that engages the second end of the pipe and further includes a male pipe section that defines a second hollow passage in fluid communication with the first hollow passage.

6. A drainage vent assembly according to claim 5, wherein the pre-existing pipework includes a female pipe end of circular cross section configured to receive and thereby retain the male pipe section of the receptacle which is dimensionally configured for insertion into the female pipe end.

7. A drainage vent assembly according to either claim 5 or claim 6, wherein the receptacle engages the second end of the pipe by further including a female pipe section having a cross sectional dimension for receiving the pipe's second end.

8. A drainage vent assembly according to claim 7, wherein the female pipe section includes a stepped cross-sectional diameter as compared with the male pipe section to thereby define the internal annular shoulder.

9. A drainage vent assembly according to claim 8, wherein the at least one spacer includes first and second annular sealing members located between overlapping walls associated with the second end of the pipe and receptacle, the first annular sealing member maintaining a longitudinal distance between the second end of the pipe and the internal annular shoulder, and a radial distance between the overlapping walls, and the second annular sealing member also maintaining a radial distance between the overlapping walls at a longitudinally spaced apart location from the first annular sealing member.

10. A drainage vent assembly according to claim 9, wherein the first annular sealing member includes a uniform outer diameter that substantially corresponds with an internal diameter of the receptacle female pipe section such that the first annular sealing member is capable of location in the female pipe section of the receptacle adjacent the annular shoulder.

11. A drainage vent assembly according to claim 10, wherein the first annular sealing member includes a non-uniform internal diameter such that the first annular sealing member includes: a flanged base portion that extends radially inwardly, and an upper non-flanged portion, the flanged base portion having a smaller internal diameter as compared with the upper non-flanged portion and thereby defining an annular shelf upon which the second end of the pipe sits such that the annular shelf maintains the longitudinal distance between the second end of the pipe and the internal annular shoulder whilst the upper non-flanged annular portion maintains the radial distance between the second end of the pipe and the female pipe section of the receptacle.

12. A drainage vent assembly according to claim 11, wherein the second annular sealing member includes a uniform internal diameter of a dimension that substantially corresponds with an outer wall diameter of the second end of the pipe.

13. A drainage vent assembly according to claim 12, wherein the outer diameter of the second annular sealing member is non-uniform such that the second annular sealing member includes: a flanged upper portion that extends radially outwardly, and a lower non-flanged portion, the flanged upper portion having a greater external diameter as compared with the lower non-flanged portion and thereby creating a lip over an upper most edge of the receptacle female pipe section, wherein an outer edge of the flanged upper portion sits flush with the outer wall of the female pipe section.

14. A drainage vent assembly according to claim 13, wherein a hollow annular space exists between an outer wall of the pipe distal end and an inner wall of the receptacle female pipe section between the longitudinally spaced apart first and second annular sealing members, and a thickness of the non-flanged upper portion of the first annular sealing member substantially corresponds with a thickness of the non-flanged lower portion of the second annular sealing member, thereby causing the annular hollow space to be substantially uniform along its longitudinal length.

15. A drainage vent assembly according to claim 14, wherein the hollow annular space is filled with a non-conductive adhesive to create a thermally insulating adhesion between the fire resistant pipe and the receptacle female pipe section.

16. A drainage vent assembly according to claim 15, wherein the non-conductive adhesive is silicon adhesive.

17. A drainage vent assembly according to claim 4, wherein the pipe has a circular cross section and defines a hollow passage through which gas passes, and the connecting member is in the form of a collar having a circular cross section that engages the distal end of the pipe.

18. A drainage vent assembly according to claim 17, wherein the pre-existing pipework includes a pipe end and the collar is configured to threadably engage the pipe end.

19. A drainage vent assembly according to either claim 17 or claim 18, wherein the collar engages the second end of the pipe by further including a female pipe section having a cross-sectional dimension for receiving the pipe's second end.

20. A drainage vent assembly according to claim 19, wherein the at least one spacer includes first and second annular sealing members located between overlapping walls associated with the second end of the pipe and collar, the first annular sealing member maintaining a longitudinal distance between the second end of the pipe and the internal annular shoulder, and a radial distance between the overlapping walls, and the second annular sealing member also maintaining a radial distance between the overlapping walls at a longitudinally spaced apart location from the first annular sealing member.

21. A drainage vent assembly according to claim 20, wherein the first annular sealing member includes a uniform outer diameter that substantially corresponds with an internal diameter of the collar female pipe section such that the first annular sealing member is capable of location in the female pipe section of the collar adjacent the annular shoulder.

22. A drainage vent assembly according to claim 21, wherein the first annular sealing member includes a non-uniform internal diameter such that the first annular sealing member includes: a flanged base portion that extends radially inwardly, and an upper non-flanged portion, the flanged base portion having a smaller internal diameter as compared with the upper non-flanged portion and thereby defining an annular shelf upon which the second end of the pipe sits such that the annular shelf maintains the longitudinal distance between the second end of the pipe and the internal annular shoulder whilst the upper non-flanged annular portion maintains the radial distance between the second end of the pipe and the female pipe section of the collar.

23. A drainage vent assembly according to claim 22, wherein the second annular sealing member includes a uniform internal diameter of a dimension that substantially corresponds with an outer wall diameter of the distal end of the pipe.

24. A drainage vent assembly according to claim 23, wherein the outer diameter of the second annular sealing member is non-uniform such that the second annular sealing member includes: a flanged upper portion that extends radially outwardly, and a lower non-flanged portion, the flanged upper portion having a greater external diameter as compared with the lower non-flanged portion and thereby creating a lip over an upper most edge of the collar female pipe section, wherein an outer edge of the flanged upper portion sits flush with the outer wall of the female pipe section.

25. A drainage vent assembly according to claim 24, wherein a hollow annular space exists between an outer wall of the pipe's second end and an inner wall of the collar female pipe section between the longitudinally spaced apart first and second annular sealing members, and a thickness of the non-flanged upper portion of the first annular sealing member substantially corresponds with a thickness of the non-flanged lower portion of the second annular sealing member, thereby causing the annular hollow space to be substantially uniform along its longitudinal length.

26. A drainage vent assembly according to claim 25, wherein the hollow annular space is filled with a non-conductive adhesive to create a thermally insulating adhesion between the fire resistant pipe and the collar female pipe section.

27. A drainage vent assembly according to claim 26, wherein the non-conductive adhesive is silicon adhesive.

28. A drainage vent assembly according to any one of the preceding claims, wherein the at least one spacer comprises a non-heat conductive material.

29. A drainage vent assembly according to claim 28, wherein the at least one spacer is made of silicone rubber.

30. A drainage vent assembly according to any one of the preceding claims, wherein the first end of the pipe that is upwardly disposed when installed includes a grating having a plurality of apertures that enable entry/exit of gas.

31. A drainage vent assembly according to claim 30, wherein each of the plurality of apertures are smaller than 3mm in diameter.

32. A drainage vent assembly according to either claim 30 or claim 31, wherein, the grating includes a cap at its uppermost end which is non-apertured to prevent or at least minimize rain entry.

33. A drainage vent assembly according to any one claims 30 to 32, wherein the fire resistant pipe and associated grating is constructed of metal.

34. A drainage vent assembly according to any one of the preceding claims, wherein the vent assembly is installed with flashing at a junction between the roofline and the pipe, the flashing located above the roofline.

35. A drainage vent assembly according to any one of the preceding claims, wherein the existing pipework extends through the roofline.

36. A drainage vent assembly according to any one of claims 1 to 34, wherein the existing pipework terminates at a location below the roofline.

37. A drainage venting system including existing pipework extending substantially to a roofline for exhausting gas from the drainage system, and a drainage vent assembly according to any one of the preceding claims.

38. A method of installing a drainage vent assembly according to any one of claims 1 to 36, the method including: locating the pre-existing pipework; and from a location above the roofline, attaching the connecting member to a pipe end associated with the pre-existing pipework such that the installed drainage vent assembly, or part thereof, is disposed above the roofline subsequent to installation.

39. A method of manufacturing a drainage vent assembly according to claim 15, the method including: inserting the first annular sealing member into the receptacle female pipe section until the flanged base portion thereof abuts with the internal annular shoulder; inserting the pipe until the pipe's second end abuts the flanged base portion to temporarily retain the pipe's second end with said longitudinal and radial distances substantially maintained, subsequently applying the non-conductive adhesive to the hollow annual space between the outer wall of the pipe's second end and the inner wall of the receptacle female pipe section, subsequently causing the second annular sealing member to engage the upper most edge of the receptacle female pipe section, and wherein, upon curing of the non-conductive adhesive, the pipe is secured in a position in which no direct contact occurs with the receptacle.

40. A method of manufacturing a drainage vent assembly according to claim 26, the method including: inserting the first annular sealing member into the collar female pipe section until the flanged base portion thereof abuts with the internal annular shoulder; inserting the pipe until the pipe's second end abuts the flanged base portion to temporarily retain the pipe's second end with said longitudinal and radial distances substantially maintained, subsequently applying the non-conductive adhesive to the hollow annular space between the outer wall of the pipe distal end and the inner wall of the collar female pipe section, subsequently causing the second annular sealing member to engage at the upper most edge of the collar female pipe section, and wherein, upon curing of the non-conductive adhesive, the pipe is secured in a position in which no direct contact occurs with the collar.