Water damage is consistently among the most frequent and most expensive household insurance claims. Not floods — ordinary internal water: a failed washing machine hose, a slow leak under a sink, a water heater reaching the end of its life, a pipe that split during a cold snap.
The expensive cases are almost never the dramatic ones. A pipe that bursts spectacularly gets noticed immediately. A slow leak behind a cupboard runs for weeks, and by the time anyone notices, the floor, the subfloor, and the wall are all involved.
What changed in 2026
- Sensor prices fell further. Basic sensors became cheap enough to place liberally.
- Insurer incentives spread. More insurers offered discounts for leak detection systems.
- Automatic shutoff became more accessible. Valve systems that stop the supply became easier to install and less expensive.
- Integration improved. Sensors working with mainstream smart home platforms simplified alerting.
Where to place them
Water appears at the lowest point near the source, which makes placement fairly predictable.
| Location |
Why |
| Under the kitchen sink |
Supply and waste connections |
| Under bathroom sinks |
Same |
| Behind or under the washing machine |
Hose failure is a classic |
| Under the dishwasher |
Same |
| Beside the water heater |
End-of-life failure is common and substantial |
| Near the main stopcock |
Where supply enters |
| Basement or lowest floor |
Where water collects |
| Under the boiler |
Where applicable |
| Near any appliance with a water line |
Refrigerator ice makers, filters |
The water heater deserves particular attention. They fail predictably at end of life, they hold a large volume, and they are frequently in a location nobody visits — a cupboard, a loft, a garage.
Washing machine hoses are the other classic: they fail under pressure and can discharge continuously.
Alerts must reach someone
The property that determines whether a sensor is useful.
A sensor that beeps locally is helpful when someone is home and useless when the house is empty — which is precisely when a leak runs longest. A leak starting the day a household leaves for a week is the worst case, and a local alarm addresses none of it.
Sensors that connect to your network and send a notification to a phone are the version worth having. That means checking connectivity where the sensor sits, since basements and utility cupboards are frequently poor for wireless signal.
Battery life matters too. A sensor with a dead battery is decoration, so choose ones that report low battery rather than simply going quiet — see home network segmentation for where these devices belong on your network.
Automatic shutoff
The substantial upgrade, and the one that changes the outcome rather than the notification.
An automatic valve fits on the main supply and closes when a sensor detects water, or when the system detects unusual flow. That stops the water rather than telling you about it.
The difference is large. A notification while you are on holiday abroad means the leak continues until someone can attend. A shutoff means it stops in seconds.
Some systems also detect anomalous flow patterns — continuous flow suggesting a leak, or unusually high usage — which catches leaks no point sensor is positioned for.
Installation typically requires a plumber, and the cost is meaningful relative to individual sensors. Against the cost of a serious water damage claim, and the disruption of repairs, it is usually favourable — and many insurers discount for it.
Common mistakes
- Local-alarm-only sensors. Useless when nobody is home.
- Too few sensors. They cost little; place them liberally.
- Not testing them. A sensor that has never been tested is an assumption.
- Ignoring the water heater. Predictable, substantial failure.
- Poor connectivity at the sensor location. Alert never arrives.
- Not replacing appliance hoses. They have a service life.
- No shutoff plan. Knowing where the stopcock is, and that it turns, matters.
FAQ
How many do I need?
One near each water source is the target. Given how inexpensive they are, over-covering is cheap insurance and under-covering is the common state.
Do insurers discount for these?
Many do, particularly for automatic shutoff systems. Worth asking, since the discount can offset a meaningful part of the cost.
Do I need smart ones?
For alerts to reach you when away, yes. A basic local alarm is better than nothing and misses the scenario that causes the most damage.
What about freeze detection?
Some sensors also report temperature, which warns of freezing conditions before a pipe splits. Useful in cold climates and in unheated spaces.
Where to go next
For where these devices belong on your network, read home network segmentation. For the maintenance that prevents leaks in the first place, filter replacement schedule and appliance lifespan.