GB2365608A

GB2365608A - Water leak alarm

Info

Publication number: GB2365608A
Application number: GB0107132A
Authority: GB
Inventors: Michael James Mowbray Rous
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-03-21
Filing date: 2001-03-21
Publication date: 2002-02-20
Also published as: GB0107132D0; GB0006855D0

Abstract

A device for detecting a water leak in a building, such as in a bathroom, consists of a rectangular absorbent mat 3 and a plurality of electrodes 5 which connect to an alarm 4. The mat 3 can be made of any suitable absorbent material such as synthetic sponge or fabric, or cotton fibres, which could be prepared and stored as a roll, and is also soaked in, or sprayed with, a salt solution to provide a source of ions. The electrodes 5 are in the form of spaced conductive wires parallel to the sides 8 and 9 of the mat 3 to ensure that substantially the entire mat 3 is responsive to leaks. The alarm 4 is an audible and/or visual unit and may be mains or battery powered.

Description

<Desc/Clms Page number 1> APPARATUS FOR DETECTING WATER LEAKS This invention relates to the detection of leaks, in particular the detection of water leaks in buildings.

As long as buildings have been supplied with water, water leaks are an all too common occurrence. The problem is that such water leaks are in places where detection is not readily possible so that damage occurs over a period of time which could otherwise have been prevented if the water leak had been noticed earlier. Whilst water leaks can occur anywhere in a building where water is supplied and used, the locations where the supply lines are connected to washing facilities such as showers and baths, sanitary installations, and electrical appliances such as washing machines and dishwashers and where water is drained are potential sources of water leakage. Applicant's business is concerned with maintenance, redecoration and repair of buildings not only as a result of wear but also as a result of damage to property caused by water leakage and fire. During the course of its business, Applicant has noticed that damage to property caused by water leakage is far, far in excess of that caused by fire. Indeed, during the last twelve years, Applicant has carried out hundreds of jobs each year repairing and redecorating property after water leaks, some so serious as to involve floods. On the other hand, Applicant has carried out only one repair and redecoration as a result of fire damage. Even though the need for repair and redecoration as a result of fire is rare, Applicant has noticed that the majority of houses have, on average, two or three smoke detectors. Whilst this is understandable because of the all-important necessity to prevent loss of life which must always be paramount, the same care and attention has never been shown, in Applicant's knowledge, to the prevention of costly and disruptive damage caused by water leaks. Furthermore, Applicant has noticed that the majority of incidents involving damage due water leaks could have been prevented had there been an early warning system, such as is provided by smoke detectors in the event of fire. Therefore, it will be appreciated that overall the costs of repair and redecoration as a result of water damage far exceeds the costs of repair and redecoration as a result of fire damage. As can be imagined, this is particularly pertinent for insurance purposes.

Applicant has noticed that there are far more common trouble spots for leaks than would have first thought to be possible. For example, cracking of the seal where the bath meets the bathroom wall allows water to leak through, particularly when the bath is used for a shower. Leaks often appear in the areas where waste pipes and overflow pipes join the bath trap under the bath. Because a bath is usually boxed in with a bath panel, such leaks are not immediately noticed.

Shower pumps are notorious for leaks, particularly on reaching the end of their working life. Again, any leaks will not detected because the pump is out of sight behind a bath panel or in a cupboard and will often be covered to reduce noise.

Back-to-wall toilet pans and concealed cisterns are another potential danger site. Pan and flush pipe connectors deteriorate and leak but, because they are boxed in, any such deterioration and leaks are not noticed. Inlet and overflow pipes will often have leak problems which are not observed.

Shower units and cubicles have their own leakage problems when the grouting decays between the tiles, or the silicon seal around the shower or cubicle tray cracks, or the connectors to the thermostatic shower unit perish or work loose.

Unfortunately, such leaks more often than not go on for a long time before they are finally noticed as discolourations on the ceiling of the floor below in a two or more storey building, dampness and rotting of adjacent timber structures such as floorboards and panelling, and lifting of the plaster in the next room sharing a common wall.

The kitchen or utility room in a building is another potential trouble spot where washing machines and dishwashers have been found to be regular causes of water leaks, either from the machine itself or from connecting pipes or waste pipes and joints. Again, because pipework is hidden behind the machine or the machine is a part of a fitted unit, leaks are not seen until the result of the leak is acute and obvious.

Radiator valves are notorious for leaking. Water trickles down the copper pipes and soaks into the flooring, such as carpet, the leak remaining unnoticed until the flooring has become damp and discoloured. Replacement of the damaged flooring will usually be necessary.

Lastly, leaks occur in roof and loft spaces from water tanks and missing and cracked roof tiles letting in water from the outside. Such leaks often go unnoticed until many tiles are lost or a large volume of water has leaked into the roof space. Because some of these leaks may be slight, it may be years before they are noticed, by which time ceiling joists and beams, as well as the ceiling itself, may have become saturated with water and require replacing. Replacement of the ceiling joists and beams is very expensive and if redecoration of the room below is necessary, costs are further increased.

Accordingly, the main object of the present invention is to detect water leaks in a building before they have a chance to cause costly and disruptive damage.

To this end and from one aspect, the invention resides in a device for detecting a water leak in a building, which would normally pass unnoticed, comprising means responsive to a water leak to alert an occupant of the building that a leak has occurred in time to take preventative action against damage, said means comprising a support formed by an absorbent mat which carries both a source of ions and a plurality of electrodes, the electrodes being connected to an alarm whereupon the completion of an electric circuit by ionic transfer initiates the alarm.

The alarm may be an audible and/or a visual alarm and may be battery or mains operated.

By means of the invention, potential sources of water leaks that are concealed by boxing, panels, ceilings etc are simply, quickly and easily detected.

To facilitate installation of the device and for ease of manufacture, the device advantageously comprises a support which is placed beneath the potential leakage source and which carries a source of ions and plurality of spaced apart electrodes

connected to the alarm. When water leaks onto the support, the ions are dissolved whereby the water containing the source of ions completes the circuit between the electrodes and thus actuates the alarm.

Applicant has found that a highly convenient way of providing a suitable support is to use an absorbent synthetic material which can be of any suitable dimensions consistent with providing sufficient detection capabilities. In such case, the electrodes may be lengths of a suitable conductive material such as copper disposed in spaced apart, parallel relationship. Ideally, the conductive material imparts a degree of flexibility to the electrodes to facilitate disposition of the support in locations which are difficult to access.

Moreover, in a preferred embodiment of the invention with electrodes having a degree of flexibility and for ease of providing supports in a wide range of situations in a building, the device can be assembled on site from a roll of support material including the electrodes from which each support is cut to a size dependent upon the location. Once the support is cut, suitable electrical connectors can be joined to one of the ends of the electrodes with the other ends left free and connected to connecting leads to the alarm.

The electrodes may be carried by the support in any suitable way, for example, by threading them through the material, by embedding them in the material between the opposite faces of the support or alternatively by laminating the electrodes in between layers of material.

Applicant has found that a simple and convenient source of ions is common salt (sodium chloride) with which the support material is impregnated or coated. However, any other suitable source of ions may be used.

From another aspect, the invention also resides in any one or more of the devices defined hereinabove when positioned in a building.

In order that the invention may be more fully understood, reference will now be made, by way of example, to the accompanying drawings, in which:-

Figure I is a diagrammatic perspective view from above of a device for detecting water leaks made in accordance with the invention; Figure 2 is a diagrammatic perspective view from one end of the device of Figure 1; Figure 3 is a diagrammatic cross-section taken along the line 111-III of Figure 1; Figure 4 is a diagrammatic cross-section similar to Figure 3 of a modification of the device; Figure 5 is a diagrammatic cross-section similar to Figure 3 of another modification of the device; and Figure 6 is a diagrammatic cross-section similar to Figure 3 of another embodiment of the device; and Figure 7 is a diagrammatic view of a bathroom showing the device of Figure I in position to detect water leaks.

Referring to Figures 1, 2 and 3, there is shown a device, which is generally indicated at 1, for detecting a water leak in a building, such as in a bathroom 2 of the building, which leak would normally pass unnoticed. The device 1 comprises means responsive to the water leak in the form of a support 3 connected to an alarm 4 to alert an occupant of the building that a leak has occurred in time to take preventative action against damage.

The support 3 is in the form of a rectangular absorbent mat having a degree of thickness. The thickness of the mat 3 may be determined by various criteria including, for example, the material that the support is made from, the intended location of the device I and/or the level of absorbency required. Accordingly, any suitable material that has a degree of absorbency, such as synthetic sponge or fabric, or cotton fibres may be used. For ease of manufacturing and distribution, the device 1 is ideally

prepared in a rolled format. Therefore, the support material should be amenable to being prepared and stored as a roll.

A further criteria for the support material is its ability to carry a source of ions. For example, a synthetic sponge or fabric may be impregnated as by soaking in, or coated as by spraying, with a salt solution before it is rolled. Alternatively, the end user may be provided with instructions to prepare the mat 3 by soaking or coating it in a suitable solution before drying and installing the device 1.

The mat 3 is provided with six elongate electrodes 5 in the form of conductive wires, e.g. of copper, that extend between opposite ends 6, 7 and are arranged in a spaced apart, parallel relationship with respect to the sides 8, 9 of the mat 3 to ensure that the substantially the entire mat 3 is responsive to leaks. As can be seen from Figures 2 and in particular Figure 3, the electrodes 5 are embedded in the support material of the mat 3. This can be done by pushing the lengths of wires through the support material which yields to allow the electrodes 5 to pass.

In an alternative construction shown in Figure 4, the mat 3a comprises two layers 10, I I of support material which are laminated by suitable means such as a waterproof adhesive or stiching. The electrodes 5 are supported within the mat 3a in between the two layers 10, 11 of support material.

The electrode wires 5 are exposed at one end 7 of the mat 3 for connection to an alarm 4 and power supply (not shown) via suitable connectors 12. As will be appreciated, the electrodes 5 are connected in pairs to the positive and negative terminals of a battery operated alarm 4. The alarm 4 is constructed to emit an audible alarm signal in the form of an intermittent bleep when the charge runs low and indicating that the battery need replacing.

While it is preferred that the mat 3 presents an absorbent under surface 13 when in use so that any water running along the area on which the mat 3 rests is absorbed by the mat 3, the mat 3 may include a water-impermeable sheet 14, as shown in the modification of Figure 5. The water-impermeable sheet 14 is laminated by a suitable waterproof adhesive to the under surface 13 of the mat 3b. Generally, this

construction ensures that any water resulting from the leaks in the form of intermittent drips will be retained within the mat 3a, thereby facilitating completing of the electrical circuit and decreasing the response time for actuating the alarm. The inclusion of a water-impermeable sheet 14 also helps maintain the dimensional stability of the device I over time.

In order to ensure maximum sensitivity and according to another embodiment of the device as shown in Figure 6, the mat 3c carries electrodes 28 in the form of respective layers of mesh sandwiched between three absorbent layers 25, 26 and 27 such that the mat 3c resembles a triple-decker sandwich. The upper (as illustrated) mesh electrode 28 is connected to the positive terminal of a battery-operated alarm 4, and the lower (as illustrated) mesh electrode 28 is connected to the negative terminal of the battery operated alarm 4. As with the wire electrodes 5, the mesh electrodes 28 are made of a suitable conductive material.

To install the device 1, the mat 3 is placed in the desired location, such as shown in Figure 7 underneath a bath 15. This location includes some of the potential trouble spots for leaks, such as water pipes 16 to bath taps 17 and shower 18, overflow and waste pipes 19, 20 from the bath 15 joining a bath trap 21, a shower pump 22, and seals extending along and between the bath 15 and walls 23, some of which are hidden behind panelling 24.

The alarm 4 is fixed to the wall 23 above the bath 15 and shower 18. However, it will be appreciated that the alarm 4 may be located in any other suitable location in the bathroom or indeed outside the room including the device 1.

In the event of a water leak, the support material of the mat 3 will absorb water from the site of the leak. As the mat 3 becomes wet, salt impregnated in the support material will dissolve in the water to provide a salt solution capable of carrying an electric current. When the mat 3 becomes sufficiently wet to the extent that the salt solution is able to carry an electric current, the electrical circuit between two or more electrodes 5 will be completed and the alarm 4 will be activated, thereby alerting the occupants of the building that a leak has occurred.

Although the invention has been particularly described it will be appreciated that various modifications may be made without departing from the scope of the invention as defined in the appended claims. For example, the absorbency of the device I may be tailored for specific locations depending on the amount of water likely to result from a leak and how quickly an alert should be raised. As another example, the device I may be supplied in a variety of forms such as a standard size, a range of sizes, with or without an alarm, or as a kit to be assembled by the end user.

The electrodes 5 may be arranged in a variety of formats: indeed, in the case of the support being non-absorbent and carrying a coating of a salt, the electrodes 5 may be in the form of a printed circuit.

Instead of the electrodes 5 being embedded within the thickness of the mat 3, the electrodes 5 may be threaded between the upper and lower surfaces of the mat 3. Moreover, the electrodes 5 may be nearer the upper surface or nearer the lower surface instead of being in the middle of the mat 3 as shown.

While it is envisaged that the device I is provided with a mat 3 with the electrodes 5 already in place, embedded within the mat, the end user may be provided with a kit to assemble the device 1. In this way, lengths of suitable electrode wire may be provided to be threaded through the support material of the mat 3, either guided by conduits (not shown) or merely by pushing the electrode wire through the support material of the mat 3.

The conductive material of the electrodes 5 will be determined by the form of the product provided to the end user. For example, the electrodes 5 must be made from a conductive material with a higher degree of strength if the end user is required to pass the electrodes 5 through the support material of the mat 3 without the aid of guiding conduits compared to a conductive material which is threaded through a conduit at the point of installation or is embedded in the support material of the mat 3 during manufacture of the device 1.

Whilst an audible alarm such as a bell or buzzer is of choice, any other suitable alarm may be used, for example a flashing light or a display panel. Instead of being battery powered, the alarm may be powered by mains electricity, via a transformer.

A number of devices 1, 1 a maybe disposed at a number of locations around a building and linked to a central panel which includes indicators allowing identification of the location where a device 1, la which has been triggered by a water leak.

Claims

Claims 1. A device for detecting a water leak in a building, which would normally pass unnoticed, comprising means responsive to a water leak to alert an occupant of the building that a leak has occurred in time to take preventative action against damage, said means comprising a support formed by an absorbent mat which carries both a source of ions and a plurality of electrodes, the electrodes being connected to an alarm whereupon the completion of an electric circuit by ionic transfer initiates the alarm.
2. A device as claimed in claim 1, wherein the mat comprises a plurality of laminated layers, of which at least one is an absorbent material.
3. A device as claimed in claim I or claim 2, wherein the mat is provided with a water-impermeable backing layer.
4. A device as claimed in any one of claims I to 3, wherein the absorbent mat is impregnated with a source of ions.
5. A device as claimed in any one of claims I to 4, wherein the source of ions is common salt (sodium chloride).
6. A device as claimed in any one of claims I to 5, wherein the electrodes are disposed in spaced apart, parallel relationship with respect to sides of the support.
7. A device as claimed in any one of claims I to 6, wherein the electrodes are lengths of a conductive material, such as copper.
8. A device as claimed in any one of claims I to 5, wherein the electrodes are in the form of layers of mesh made of a suitable conductive material, sandwiched between layers of absorbent material of the mat.
9. A device as claimed in claim 7 or claim 8, wherein the conductive material imparts a degree of flexibility to the electrodes.

<Desc/Clms Page number 11>
10. A device as claimed in any one of claims I to 9, wherein the alarm is an audible and/or a visual alarm and is battery or mains operated.
11. A device as claimed in claim 10, wherein the alarm emits a signal when the battery is low.
12. A device for detecting a water leak in a building which would normally pass unnoticed, substantially as hereinbefore described with reference to, and as shown in, Figures 1 to 3 of the accompanying drawings.
13. A device for detecting a water leak in a building which would normally pass unnoticed, substantially as hereinbefore described with reference to, and as shown in, Figures I to 3 as modified by Figure 4 of the accompanying drawings.
14. A device for detecting a water leak in a building which would normally pass unnoticed, substantially as hereinbefore described with reference to, and as shown in, Figures I to 3 as modified by Figure 5 of the accompanying drawings.
15. A device for detecting a water leak in a building which would normally pass unnoticed, substantially as hereinbefore described with reference to, and as shown in, Figure 6 of the accompanying drawings.
16. A device as claimed in any one of claims 12 to 15 when positioned in a building, substantially as hereinbefore described with reference to, and as shown in, Figure 7 of the accompanying drawings.