top of page

Water Leak Detection Alarms


Recent years have seen considerable growth in the development and use of a variety of water leak detection systems, aimed at mitigating the risk of burst or leaking plumbing systems and other water services in residential, commercial and other property sectors. When installed and maintained correctly, such equipment can have a significant impact in terms of risk control.

This Technical Bulletin aims to provide Consultants with a greater awareness of the type of products available and to define the RiskSTOP approach to water leak detection going forward.



A wide range of equipment is available for various applications from a simple, standalone mains or battery powered device consisting of a linear water sensing cable and audible warning device (in some cases coupled with SMS text messaging), to more complex 100+ zone systems with visual control equipment employing both linear detection cables and spot sensors/probes and detection pads. Via the use of zone location modules when employing detection cable, or the use of individual probes, systems are able to pinpoint the leak to a specific area. Such systems are often integrated with the building management system and provided with remote

signalling to an alarm receiving centre.

In addition to providing both local and remote audible and visual alarms, water leak detection systems can, very importantly, be incorporated with solenoid or motorised ball operated shut off valves which automatically isolate the water supply upon detector activation. Where required, facilities can also be incorporated to switch on sump pumps, shut down process equipment, switch off power supplies, etc.

Typical components of a water leak detection system

A range of detection sensors/probes

A range of solenoid shut off valves

Potential applications for water leak detection are extremely wide and include:

  • Critical data and telecoms facilities

  • Archives stores

  • Museums, libraries and galleries

  • Historic buildings

  • Hospitals

  • Hotels

  • Plant rooms

  • Vending areas

  • Luxury apartments and prestigious houses

  • Student accommodation.

Some installation examples:

Water sensing cable clipped to the slab within a raised floor

Water sensing cable fitted in a high-level drip tray

Probe fitted within the base of a service riser or lift pit to detect water ingress

Probe and detection cable installed in plant rooms

Simple single zone systems are capable of DIY installation or can be easily installed by competent contractors involving a total cost of under £1,000.  However, more complex systems and particularly those, for example, protecting major IT or telecoms facilities should be designed and installed by a company specializing in this field such as:

Further information is available from the websites listed.

As with other protection installations, leak detection systems should be inspected and tested as part of routine maintenance, for which a period of once every 12 months is the normal expectation. Complex systems such as those protecting dealing rooms or major libraries will often be inspected more frequently.

Unfortunately, there are no British or European Standards relating to the design and installation of water leak detection systems and there are no product approval schemes in operation. However, this should not detract RiskSTOP from recommending the installation of such products under the conditions detailed below.


(In addition to the range of products highlighted above, there are an increasing number of domestic water leak detection/alarm devices available online. Whilst these may have some merit, they are not envisaged for commercial use.) 



In addition to sensing a water leak, a range of flow-based detection devices are also available designed to minimise the amount of water allowed to escape should a pipe burst or leak. Installed just after the stopcock, these devices measure the flow of water passing into the property and compare the flow rate and time the water has been flowing against user definable settings. In the event that either setting is exceeded, a motorised ball valve will automatically close and isolate the water system. These commonly also incorporate a “holiday mode” whereby the valve automatically closes after no water flow is detected in a set period.

Whilst mainly intended for residential property, these may on occasions have an application in other areas such as small retail or commercial premises, and those involving partial occupancy such as sports pavilions.


An example of a flow-based detector

A company which is actively marketing their electrically operated water isolation valves and leak detection devices in the insurance sector is LeakSafe Solutions Ltd ( They have submitted their WaterSwitch and LeakSafe products to the BRE for testing, where they have been successfully validated for functionality and durability. As a result, their products, which are summarised below, have been endorsed by several UK High Net Worth Insurers:

  • WaterSwitch2 – a wired, or wireless motorised ball valve installed on the incoming mains water supply, providing an easy and accessible method of isolating the supply when leaving the premises. The wireless option incorporates a delay function of between 1 and 3 hours allowing, for example, washing machine and dishwasher programmes to finish.

  • Leak Detector – wireless leak detectors installed in conjunction with WaterSwitch, providing automatic closure of the ball valve when water is detected.

  • Flow Guard (WaterSwitch2-F) – consists of a motorised ball valve, flow sensor and control panel. If the sensor either doesn’t see water flow and/or sees continuous water flow for a programmable time period it will turn the water off. These features are particularly suited for second homes, holiday rental properties, vacant premises, or construction sites.

The WaterSwitch2 optional relay module can connect to existing intruder alarm systems, GSM auto-diallers for SMS or email notifications or BMS systems (building management systems) to raise a remote alarm if a leak is detected in the property.

LeakSafe products were originally developed for domestic use, but are also now marketed for the commercial sector.

It is important to recognise that any detection system which involves the automatic isolation (whether intended or otherwise) of an essential water supply on which safe running of plant and equipment is dependent, may present a fire/explosion or machinery breakdown hazard. In these circumstances, careful consideration at the design stage may be required. In respect of unwanted activations from false alarms/equipment malfunction, these, by reference to the equipment supplier/installer, are normally capable of being engineered out.



In circumstances where meritable water detection systems are encountered in the field, details are to be included in the report as a positive risk feature. Also, with any systems of size or significance, enquiries as regards the arrangements for essential servicing and maintenance are to be made.

Unless driven by a specific CSI, risk improvements for the installation of a water leak detection system shall be selective and made following a risk assessment in which factors such as the size, extent and condition of the water services and equipment, the building occupancy, susceptibility to damage and incident history are to be considered, together with the MD/ BI exposures.

Except in extreme situations (including post loss), such risk improvements, where raised, are normally to be submitted as Recommendations.

bottom of page