Water leak detection that shuts the water off for you
A few Zigbee leak sensors, a motorized valve on the main water line, and one local scene: the water is off seconds after a leak, even if nobody is home.
Water damage and freezing are among the most common home insurance claims in the US, with an average claim of about $15,400 according to the Insurance Information Institute. A leaking water heater or a burst washing machine hose does most of its damage in the hours nobody notices, and a leak sensor that only beeps doesn't help much when you're at work or on vacation.
With Gladys Assistant, a free and open-source smart home platform that runs at home, any leak sensor can close a motorized valve on your main water supply, send you an alert on your phone, and switch off the appliances involved. It runs locally, so it reacts even when the internet is down, and there's no monthly fee.
Why a beeping sensor isn't enough
Most leak detectors on the market have the same limits:
- They alert you, but nothing stops the water until someone comes home.
- Smart shutoff systems often require their own hub, app and sometimes a subscription.
- Cloud-based systems depend on the internet and the vendor's servers to react.
- Each brand works in its own app, so the sensor under the sink can't talk to the valve from another brand.
What you really want: any sensor, any valve, one rule that always runs. That's a job for local home automation.
What you can build with Gladys
Leak sensors and valves become regular Gladys devices:
Under sinks, behind the washing machine, next to the water heater and the boiler: Zigbee leak sensors are small, cheap and run for years on a battery.
A motorized valve on the main line closes as soon as any sensor detects water, without waiting for you.
A Telegram message, an SMS or another notification channel tells you which sensor triggered.
Turn off the smart plug of the washing machine or the dishwasher involved, in the same scene.
Battery levels are tracked like any other value: a scene can warn you when one runs low, and the weekly AI report (Gladys Plus) flags sensors that went silent.
Sensors, valve and scene all run on your local network: the shutoff happens even if the internet is down.
How to set it up
On a mini-PC or a Raspberry Pi running Gladys:
- Add a Zigbee coordinator and enable Zigbee2MQTT in Gladys.
- Pair Zigbee leak sensors (Aqara, Third Reality, Sinopé WL4200, Tuya and many others are supported by Zigbee2MQTT) and place them where leaks happen.
- Install a motorized valve on the main water line, such as a Sinopé Sedna valve, the Aqara Valve Controller T1 or another Zigbee valve controller supported by Zigbee2MQTT, and pair it.
- Create a scene: when any leak sensor detects water, close the valve, send a notification and turn off the related appliances.
- Test it with a damp cloth on a sensor, and check that the valve closes.
Have a plumber install the valve on the main line if you're not comfortable doing it yourself.
Any sensor, any valve, one local rule
Because Gladys talks to Zigbee, Z-Wave, Matter and Wi-Fi devices, you're not tied to one brand's kit: mix the sensors and the valve that suit your home and budget.
Gladys is free and open source. Gladys Plus, optional, adds encrypted remote access and backups, but the shutoff itself never depends on it.
Go further
Protect your home with local automations:
Frequently asked questions
Can a smart leak sensor shut off the water automatically?
Yes, if it's paired with a motorized valve on the main water line. With Gladys Assistant, any supported leak sensor can trigger a scene that closes the valve, sends you an alert and turns off appliances, locally and without a subscription.
Does automatic water shutoff work without the internet?
With Gladys, yes. The Zigbee sensors, the valve and the scene all run on your local network, so the water is shut off even if your internet connection is down. Only the remote notification needs the internet.
Which leak sensors and valves work with Gladys?
Any Zigbee leak sensor or valve controller supported by Zigbee2MQTT, such as Aqara, Third Reality and Tuya leak sensors, Sinopé WL4200 sensors, Sinopé Sedna valves and the Aqara Valve Controller T1. Matter and Z-Wave devices can be used too, depending on their features.
Where should I put water leak sensors?
Wherever water can leak: under kitchen and bathroom sinks, behind the washing machine and the dishwasher, next to the water heater, the boiler and the water softener, and near the main water inlet.
Is there a monthly fee?
No. Gladys is free and open source, and the sensors and valve are one-time purchases. Gladys Plus is optional, for encrypted remote access and backups.
Stop leaks before they become floods
Gladys is free, open source and installs with a single Docker command. Pair your sensors and your valve, and let the scene watch your home.