AU2005100313A4 - A new one-piece rainwater gutter profile which is not prone to blockage by tree debris - Google Patents

Description

Australia Patents Act 1990 COMPLETE SPECIFICATION INNOVATION PATENT A NEW ONE-PIECE RAINWATER GUTTER PROFILE WHICH IS NOT PRONE TO BLOCKAGE BY TREE DEBRIS.

A NEW ONE-PIECE RAINWATER GUTTER PROFILE WHICH IS NOT PRONE TO BLOCKAGE BY TREE DEBRIS There is an inherent problem with conventional rainwater guttering, in particular guttering which is used to drain rainwater at the perimeters of residential-scale building roofs wherever there are trees present.

This problem is that whilst the open channel of a conventional gutter is designed to catch rainwater it also catches unwanted falling or wind-blown debris such as tree leaves, seeds, nuts and twigs which are a nuisance because they block the performance of the gutter. Most roofs have gutters which are fitted to the fascia boards of projecting eaves. However some roofs have no eaves at all and these are generally referred to as 'clipped eaves' or 'Tuscany' style roofs where the gutter is located immediately adjacent to the enclosed roofspace. If a building is located near or under trees it is inevitable that a conventional open channel gutter is likely to collect tree debris. Any debris which accumulates in and around the gutter shall fill the gutter channel and shall eventually block its outlets with consequent detrimental effects on the gutter's ability to drain rainwater properly. Without regular maintenance a blocked gutter will result in rainwater overflowing either onto the fagade of a building or back-flowing into the eaves overhang or worse still into the roofspace of a clipped-eaves 'Tuscany' roof If rainwater is allowed to backflow into a Tuscany styled building with clipped eaves the water damage can lead to costly repairs because the water which enters the roofspace usually filters downwards from the top of the wall even if it is a cavity wall and over and through the roof/ceiling insulation damaging not only the roof ceiling insulation but also the plasterboard ceilings, some of the timber roof members, the painted or wallpapered plasterboarded walls, the furniture, the carpets, the decorative timbers and the electrical fittings with the possible added risk and costs associated with electrical short-circuiting. Routine maintenance to clear accumulated debris before water damage occurs shall reduce the risk of these problems but the benefits of routine maintenance are often overlooked either as a result of ignorance, lethargy or cost-cutting measures. A lack of routine maintenance not only increases the risk of damage to a building through water ingress but also the damage which can be caused by fire. If accumulated debris it is not removed either manually or by wind or rain it is a very severe fire hazard. Buildings which have accumulated debris on their roofs are at a much greater risk of being consumed by the spread of fire because the accumulated debris would add combustible fuel to the flames of a fire which reaches roof eaves level. The internal roofspaces of roofs are generally are not as fire resistant as the walls of the building and if a fire reaches the eaves or gutter level of a building it shall consume the accumulated dry debris in the gutters and wherever else the debris has gathered on nearby parts of the roof and the fire will spread very quickly.

The fire will enter gaps under the bottom edges of metal sheeting roofs and between the joints of tiled roofs and then very rapidly consume the air and the combustible insulation and electrical and structural materials located within the roof space.

Any device which keeps roofs and roof-edge gutters free of debris shall: a) reduce the frequency and therefore the time and costs involved with maintenance, b) increase personal safety by reducing the number of times a person must climb a ladder in order to clean the gutters and the roof, c) reduce the risk of water damage caused by the overflowing of debrisladen gutters and roofs, d) reduce the risk of accidental, act of God or arson fire damage by reducing the amount of accumulated debris on roofs and gutters, e) reduce the risk of tainting any rainwater which may be harvested for recycling as potable drinkable rainwater by avoiding the accumulation of debris which would otherwise have rotted in the rainwater trapped within a blocked gutter.

f) and may reduce building owner insurance premiums if insurance companies recognise and accept the above benefits, Some currently marketed attachment devices have been designed by others in an attempt to protect conventional open-channel gutters from collecting debris, with varying degrees of success. Often the attachments themselves collect debris. Generally the nature of these attachments are that they are perforated to allow rainwater to pass through them and it is these perforations which permit twigs and leaf stems to become lodged through the perforations which then collect more twigs and leaves rather like a beaver's dam and consequently the debris is not wind-blown off the roof or swept away by heavy rain flow but is static enough to allow more debris to accumulate. In a short time the quantity of accumulated debris is sufficient to reduce the flow of water into the gutter and the water spills out over the outside or the inside edges of the gutter and onto the fagade of the building or into the eaves or roofspace. When this condition is reached it is well passed the time to clear the anti-debris attachment for routine pre-emptive maintenance. When clearing the debris by hand the twigs and leaf stems are often so brittle that they break off and as a result parts of them either remain securely lodged and entwined within the perforations of the attachment or break off and drop into the gutter below and they generally never get removed from the gutter because it is too awkward to remove them by hand or by tool with the attachment blocking access to part of the gutter. These smaller particles can also block the drainage downpipes at the bends in the pipes where they are unseen and ultimately can cause total blockage of not only the downpipe but also the gutter. The trapped debris is left to rot in the pipes and inside the gutter and consequently it blocks the outlets and the flow capacity of the gutter even more. This process repeats itself as additional debris falls on top of the attachment and the cycle is repeated as more and more debris accumulates yet again which also can not be removed by wind or rain because it is obstructed by collected debris. Sometimes gutters deteriorate through rusting caused by blockages which are concealed beneath the attachment device. Some alternative very shallow gutter designs have been produced in an attempt to allow debris to overflow off the edge of the gutter. These shallow gutters have upstanding outlets with small holes for drainage into a second integral, sealed and therefore concealed gutter below the upper shallow gutter. The idea is that debris collects on the upper gutter and is dispersed by either a rush of heavy rainwater or a gust of wind when conditions are dry. However the perforated outlets also suffer from debris collection and consequently become blocked with similar detrimental effects as other blocked gutters. These shallow gutters are too shallow for heavy rainfall and as a result rainwater which could have been captured and recycled is lost especially if the outlet holes are partially blocked. These too have not solved each of the problems sufficiently. Local Councils are now encouraging homeowners to collect and store rainwater for stormwater detention and/or recycling. Some homeowners collect rainwater for human consumption and need the rainwater supply to be kept drinkable (potable). If rotting debris is allowed to become trapped in the gutter it will taint the quality of the collected water. The core of the problem with all of the currently used guttering systems is that they collect debris as well as rainwater. They allow debris to collect in ways which detrimentally affect their ability to harness clean rainwater because they use drainage holes or perforations which become blocked. Also they do not permit uninterrupted or unhindered removal by wind or rain and they do not collect all of the available rainwater that could be recycled for re-use because the accumulation of debris reduces the performance of the gutter or the water catchment properties of the design of the gutter have been compromised in order to eradicate debris.

What is required to alleviate this problem is a new type of gutter which by its one-piece cross sectional design does not use perforations or outlet openings near collected debris and which protects its open gutter area as much as possible from falling or wind-blown debris whilst at the same time controlling the lodgement of debris and the movement of rainwater to best effect such that the new profile separates debris from rainwater as much as possible and then collects all of that 'debris-free-water' or 'less-debris-filled water' for recycling more than current systems are able to do but which still allows the debris to be removed from the profile in dry conditions by natural wind, or in wet conditions by heavy storm rain, and yet still does not permit that discarded debris to fall easily into the gutter.

The ideal new gutter would be a gutter which works without the use of perforated attachments or perforated upstand outlets at debris level in order to avoid blockages by debris and which is formed in such a way that it works at two open but connected levels, one above the other. The upper open level deals with the debris and the lower open level deals with the collection and redirection of rainwater. In this ideal gutter the upper open surface would be both flat and convex in a form which would temporarily detain debris by allowing the flow of rainwater to deposit the debris onto it.

The debris would cling to the smooth wet surface because at average speeds of rainwater movement over a relatively large and smooth surface there is molecular attraction between wet surfaces which will compel the wet debris to cling to the smooth wet surface of the profile whilst at the same time allowing the continued flow of rainwater over the surface of the profile because it is subject to much less friction over the smooth surface than debris is and it would continue to run by gravity downwards to the lower open gutter level further down the profile. The form of the profile can be made in such a way that it permits the flow of rainwater around the surface of the profile without losing molecular attraction to that surface even if that surface is contoured as an overhang to an extent that does not encourage water to fall off from it but rather allows water to remain in contact with it until the rainwater reaches the lower level open gutter where it is collected and is discharged by downpipes. This lower level open gutter deals with the capture and redirection of 'debris-free' rainwater or 'less-debris-filled' rainwater via outlet pipes to either stormwater detention tanks or a stormwater sewer or soakaways or to storage for recycling or human consumption. The upper open flat level of the new profile holds wet debris temporarily until it is either washed clear off the profile by very heavy rain or until it and the surface of the profile are both dry enough for the dry debris to be blown off the roof by natural wind. The location of the lower level open gutter should be overhung by the upper open level section such that any falling debris whether it is dry or wet does not fall easily into the lower section gutter and block this gutter. A two-level open system would be less likely to attract or collect debris into its lower level open gutter if the upper level is designed to project forward of and thereby overhang the lower level open gutter area sufficiently for it to shelter that gutter area from falling or gathered debris which is wind blown off the roof. In this way the design proposed in this specification differs extensively from the currently used shallow-double gutter systems because the gutter sections of the existing currently available shallow-gutter-double-gutter systems have an enclosed, integral and therefore concealed gutter beneath the upper shallow gutter level which is fed water by upstanding perforated outlets in the shallow gutter above and is not an open gutter as is proposed in this specification. The proposed design in this specification still retains the principle of an open gutter and not a concealed enclosed gutter. The proposed lower level open gutter is sheltered by an open and overhanging profile that prevents and minimises debris from falling into the lower level open gutter. The lower level open gutter in the proposed system is accessible from the outside of the building and can be cleaned as a normal gutter if necessary. The two-level open profile design of the proposed system would make it possible for the debris which is deposited on the upper level to be wind-blown away from the roof on dry days. On wet days the proposed system would make it possible for the debris to be kept in one place on the upper surface of the proposed profile by the moist resistance which shall exist between the wet debris and the wet profile. The moist debris would therefore be kept away from the lower level open gutter because it temporarily sticks to the upper surface because both the debris and the upper surface are wet and the debris shall adhere to the wet smooth surface. When the debris has dried out it is blown off the roof by natural outdoor air movement but does not fall into the gutter because the lower open gutter is much further recessed than, and is overhung by, the edge from which the debris shall fall. This lower open gutter system can then collect almost completely debris-free water. The main benefit of a two level open profile gutter system would be that it would not be prone to collecting debris in the open gutter as easily as current guttering systems are prone to be because in the proposed system the debris is collected above and away from the recessed gutter which is located underneath and the debris is then blown off the overhanging portion by wind or washed off by very heavy storm rain. Therefore the lower level open gutter which is recessed below the overhanging area would receive less debris and would require less maintenance than is currently needed by existing systems. The further benefits of this system would be that the building would be at less risk of water or fire damage and this would be reflected in lower maintenance costs for the building owners and possibly lower insurance premiums. An additional benefit would be that the water is not tainted by rotting debris and would be as clean as possible for re-use, it may even be potable if the roof finish or the atmospheric conditions have not already tainted it.

The invention described in this specification is for a new type of gutter which shall almost completely reduce the incidental and unwanted collection of debris falling into the gutter in a way which is much more effective than currently offered by all conventional gutters and their antidebris attachments.

This new gutter profile shall achieve this: a) by means of its new compound cross sectional design which overhangs and therefore shields the open gutter section located below from falling debris, b) by the shape and surface texture of the material used in its construction in order to both attract wet debris to stick to the new profile when it is wet but at the same time to allow running rainwater to run between, around, over and in some cases underneath the temporarily-adhered-debris and to continue downwards into the open gutter section below, c) by utilising the inherent physical properties of water, debris, the smooth and curved surfaces of the proposed profile and by air movement in order to achieve the desired outcome of a water supply that has little or no debris within it as it is redirected by rainwater downpipes to stormwater detention tanks, rainwater storage tanks or a stormwater sewer.

This design principle works because it encourages and utilises the following natural physical properties of the materials involved namely; water, debris, air movement, dry conditions, wet conditions and a man-made gutter surface which is designed and made in such a way that each of the ingredients of the problem shall work together in such a way that they become the solution to that same problem by the passive use of their own physical properties in ways that have not been fully utilised before. The surface of the device and its shape allow the water and debris to behave in different ways. This is because the debris has a predisposition to behave in two different ways on smooth surfaces during either wet or dry conditions.

Debris shall cling temporarily to a smooth wet surface by friction between the debris and the surface. However debris shall not cling to a dry smooth surface if both the debris and the surface are sufficiently dry to allow the debris to be blown off by the next gust of wind. The surface of the profile shall allow rainwater to pass over it because water will naturally run over smooth surfaces with little friction especially over surfaces which are already wet. Also the rate of water flow can be increased if the overhung surface is inclined at an appropriate angle. The proposed design principle passively utilises the following physical properties: a) the inherent viscosity of water, albeit a low viscosity, b) the natural attraction of water to and around smooth curved surfaces, c) the gentle curvature of the proposed profile combined with the viscosity of water in order to guide the flow of water to best effect, d) the attraction of wet debris to smooth wet surfaces and that this attraction differs in momentum from the speed of the momentum of running water as it moves over a smooth curved surface, e) the momentum of fast running heavy rain and the weight of wet debris, f) the lack of attraction between dry debris and a smooth dry surface which has been shaped to encourage the wind-blown movement of that dry debris, h) the clearing abilities of natural outdoor air movement (wind or breeze) in removing the light weight of dry debris from a smooth slightly inclined dry surface.

All of these physical properties are found in the materials and forces involved with guttering namely rainwater, tree debris, the gutter profile, the drying effects of sunshine and wind. The shape of the proposed profile is designed to utilise these natural physical properties and forces to the effect described as follows.

The proposed guttering system which we wish to patent comprises of a cross sectional profile as described below and as shown in the accompanying drawing Figure 1.

The cross sectional profile is of a double curve made from any suitably resilient solid or translucent self-finished or painted material and which when viewed from the side shown in the drawing is somewhat like that of an inverted but slightly distorted capital letter The shape of the curves of the have been stretched to create a greater undercut where the smaller lower open concave curve is set much further back from and underneath the extent of the larger upper convex curve. The upper convex curve is the area where debris is separated from the flow of rainwater. The lower open concave curve is the gutter which receives water which has been allowed to run over, around, down and underneath the larger radius upper convex curve. The larger uppermost curve 2 is flattened out at its uppermost end 1 to meet the roof sheeting or tiles (from hereon to be termed roofing material) and as such the proposed profile is not exactly a full curve as that of the capital letter The angle of this surface is one which is selected to arrest wet debris, it need not match the angle of the roofing material. Where this surface abuts the underside of the roofing material it is curled upwards and back over itself at 7 to create not only a continuous narrow surface for the roofing material 8 to rest onto and be fixed into if necessary but also creates a water-stop intended to prevent rain from being blown under the roofing material 8 and into the roofspace 11. The flattened out section of 1 is sufficiently long to attract debris. The surface of 1 is smooth in texture which further attracts wet debris to cling to it. It may also have corrugations to allow additional water drainage under raised debris if necessary. Dry debris can also settle on the surface of 1 during calm weather conditions of no wind but when the debris and the surface 1 are both sufficiently dry a gust of wind will blow this debris off 1 and beyond the crest extent of the larger upper curve 2 and well clear of the lower portion of the open gutter 4 underneath. The larger curve 2 is also smooth and even in texture and overhangs the smaller lower smooth surfaces of 3 and 4. It is this lower curve 4 which is the gutter that carries water to outlet pipes 5 or 6.

Maximum water level in the gutter is marked on the diagram as 9. Beneath the gutter 4 is a small continuous down-standing water stop drip-edge formed in the underside surface of 4 and this is designed to prevent extraneous rainwater that may strike the outer surface of the gutter from running back towards the rear of the gutter's underside and its rear faces and onto the fascia board onto which the proposed gutter would be mounted.

This drip-edge 10, and the fact that the back edge of the gutter is curved away from the fascia, shall protect the fascia board from rotting as would occur if the design was different and water was allowed to be repeatedly trapped between the back-face of the gutter and the front-face of the fascia if the back face of the gutter was vertical and matched the vertical face of the fascia. The fascia board is not shown in the diagram for purposes of clarity.

The uppermost curve 2 overhangs the lower curve gutter 4 to such an extent that almost all windblown debris shall fall off from the upper curve 2 away from the roof edge and is unlikely to fall directly into the gutter section 4.

Some dry leaves may be blown into the gutter section 4 if the wind is strong enough and blowing in an upward direction towards the gutter but this amount of debris would be much less than the amount experienced by conventional open gutters because in the proposed design the open gutter 4 is overhung and overshadowed by the large curvature of 2 which protects it from falling debris. This is a protection which current systems on the market do not have. It is possible that the material used for the construction of the gutter profile can allow for the gutter to have a translucent nature allowing the use of concealed artificial illumination behind the guttering for a unique illumination effect at roof eaves level of a building.

In this proposed process most debris is left at the top of 1 by moist friction when both the debris and the surface of 1 are wet and little debris, if any, is carried by rainwater running over the surfaces of 1, 2 and 3 into the gutter 4 because wet tree leaves cling with temporarily moist adhesion to smooth wet surfaces. Debris which has clung to the surface of 1 shall stop additional debris. The running rainwater leaves the debris behind because the debris cannot flow over smooth surfaces as readily as does water. The rainwater then runs beyond the debris either by running over it, between it or around it until it is free of the majority of the debris. The surface of 1 may require smooth or rough textured corrugations for a portion of its length ahead of and above the curve of 2 in order to keep the debris clear of and above the water flowing on the main surface of 1.This may depend on the locality and nature of the leaves falling from trees in the vicinity. The large-radius smooth-surfaced curve of 2 is curved in such a manner that rainwater shall cling to its smooth surface by viscosity, surface tension and molecular n attraction as it passes down the smooth surface of 3 until it reaches the smooth surface of gutter 4 without losing contact from any of the surfaces of 2 or 3. The surface of 2 can have some vertically arranged corrugations if they prove to be necessary to assist some soft leaf types to break moist adhesion with 2 and drop clear of 4. This is subject to the location of the building to certain types of trees with certain types of leaves. Water naturally clings to and runs easily over these continuously smooth surfaces when the surfaces are curved to be compatible with the average rate of flow of rainwater even when a surface is overhanging. That overhanging surface is angled to such a degree that the rainwater shall continue to cling to the underside of the overhanging surface sufficiently that the rainwater does not lose contact with it and therefore does not fall away from the surface until it enters to gutter 4. If no debris is present in the rainwater then even a heavy flow of rainwater can flow in constant contact with the profile's surfaces and gather in the gutter because the profile is proportioned to ensure this for Oheavy rain flow. During extremely heavy rainfall debris shall be washed straight off the roof because the speed of the flow of rainwater is greater than average or heavy rainwater flow and is sufficient to propel it clear off the edge of 2. This is because the rainwater reaches the top of 2 and loses wet adhesion with the surface of 2 because it contains large amounts of wet debris which forces the water to lose its adhesion with the surface and consequently propels itself and the accompanying clumps of debris off and away from the profile completely. The debris' wet-weight will make the wet debris drop straight down and not backwards into the gutter section 4 because the wet debris downward movement is too rapid to be blown in any other direction by wind. In the event that some types of debris may be more prone travel down the surface of 2 and 3 by being contained within the flow of rainwater more so than other types of debris there may be incorporated into the profile cross section another optional small protrusion formed in the surface of 3 at the point where the arrowhead is shown on the drawing. This additional optional protrusion may be similar in effectiveness to that of such that it creates a point at which the debris shall be arrested from running further down the surface of 3 and then force the debris to drop away from the surface of 3 by the loss of wet adhesion at that point which shall allow it to fall clear of 4. This optional additional drip must be shaped in such a way that it shall continue to permit clean rainwater to flow over it and into 4 without any loss of adhesion and as such the curvature of this optional drip may be less acute than that of the drip marked 10. Gravity leads the relatively debris-free rainwater to the open gutter section 4. The rainwater then collects in this lower open gutter section 4 and discharges out of the outlet pipes 5 or 6 which drain the rainwater to stormwater detention tanks, or to rainwater storage tanks, or to a sewer or to soakaways. Mesh filters which can trap debris which may have entered the gutter 4 can be inserted into the openings of these pipes as an optional safeguard. The number of down pipe outlet locations is calculated to meet the requirements of local council building laws. These outlet pipes can be arranged to drain either vertically or horizontally from the gutter as shown, alternative 5 is horizontal, alternative 6 is vertical. The lowest point of a horizontal outlet would be level with the lowest point of the base of the open gutter 4 to ensure that drainage and water-flow is completely unrestricted. The clumps of wet debris which have been propelled off from the extent of 2 to ground level by extremely heavy rainfall down can be cleaned up from ground level at any time. This is of benefit to personal safety because the dropped debris can be easily and safely collected at ground level by building owners or maintenance crews without the use of a ladder at eaves or roof height level as would be the case with conventional gutters. In light rain conditions tree debris shall cling to the smooth surface of the top of the upper curve at 1 and remain there until it dries out. When the debris and the surface of 1 have both dried out sufficiently the debris will be blown off the roof by the next gust of wind and because the smooth curved surfaces of 1 and 2 allow it to be blown off easily. Debris is unlikely to be blown into the lower gutter section 4 because of the amount of overhang created between 2 and 4.

During dry weather, dry debris which settles on top of the upper surface at 1 shall be blown off the profile by each gust of wind.

Claims (4)

1. This is a one-piece open rainwater gutter profile as shown in Figure 1 which by means of the connected flat and curved surfaces 1, 2 and 3 is less prone to blockages by tree debris because its open channel gutter section 4 is sheltered from falling and wind-blown tree debris by the overhanging profile at 1,2 and 3 and because the top surface of 1 is formed in such a way that it allows the collection of falling and windblown dry and/or rain-soaked tree debris to settle onto the profile at 1 from which it is blown off the roof by wind in dry weather or in wet weather is temporarily adhered to this surface by wet adhesion and is thereby separated from the flow of average rainwater over the smooth inclined flat plane of 1 such that the majority of the debris is captured at this level of the profile which promotes the collection of 'debris-free' or 'less-debris-filled' rainwater which then by its own viscosity and its own surface tension and by the forces of gravity, and Sthe inherent molecular attraction between water and smooth surfaces runs N over the surfaces of 1, around 2, and down 3 without losing its molecular surface attraction to any of these surfaces especially that of the overhanging portion 3 and into the open gutter section 4 at the lower area of the profile from where it can be redistributed by pipes to either stormwater detention tanks or rainwater sewers or soakaways or to rainwater storage tanks for recycling or for human consumption because the water is clean of tainting debris.

2. This is a rainwater gutter profile as referred to in Claim 1 which requires less frequent cleaning maintenance because of its cross-sectional profile design which separates debris from rainwater and permits the dispersal of debris by natural forces such as wind and rain without human intervention.

3. This is a rainwater gutter profile as referred to in Claiml which allows dry debris to settle at 1 from where it can be blown off the roof by wind and does not attract that dry windblown debris to fall into the lower open gutter section 4 of the profile because that open gutter is overhung by the profile 2 above it.

4. This is a rainwater gutter profile as referred to in Claiml which gathers and attracts wet debris at 1 until that debris is dry enough for it to be windblown off the roof and does not attract that same dry debris to fall into the lower open gutter section 4 of the profile because that open gutter is overhung by the profile 2 above it. This is a rainwater gutter profile as referred to in Claim 1 which in stormy weather gathers and clumps together large quantities of wet debris at 1 and which then permits the fast pace of very heavy rainfall to ejects the clumps of debris off the extreme edge of the profile at 2 by momentum and prevents the debris from falling into the lower open gutter section 4 of the profile because the portion of the profile from which the clumps of debris shall lose moist adhesion is sufficiently beyond the lower level open gutter 4 area to avoid capture of that falling wet debris by that open gutter area 4.