Fire might be a homeowner’s greatest fear, but any insurance company will tell you that water is the far more common cause of property damage, even if you don’t live in an area subject to flooding. And it can come from many sources: A failing water heater, a burst pipe, a broken supply line under your sink, a clogged toilet, or even a split hose connected to your washing machine.
Just as it’s essential to have a smoke detector in each of your home’s bedrooms and common areas, you’d be wise to install leak detectors in places where water damage could start: The laundry room, water heater closet, the bathroom, under your kitchen sink, and so on. Leak alerts are arguably less important for renters, but it’s something landlords might want to consider—although that raises the issue of how the sensors would connect to the internet. More on that later.
If you think a leak sensor is something your home should have, here are our top picks. If you want more information on this topic and want to read more reviews, scroll down a bit.
Updated May 15, 2024: We’ve added a link to our Flo Smart Water Monitor & Shutoff review. Moen’s second-generation smart valve displaces the second-generation Phyn Plus as our most highly recommended leak prevention system, thanks to its being a part of Moen’s larger Smart Water Network. We also like the all-but-impossible-to-ignore robocalls that Moen’s system makes when its device suspects there’s a leak in your main water and before it proactively shuts its main valve off to prevent catastrophic damage. These types of smart home device are expensive and typically require professional installation, but their cost is a fraction of what it would cost to clean up and repair the water damage caused by a burst pipe.
Top picks in water leak detection and mitigation
Moen Smart Water Leak Detector — Best smart water leak detector
Pros
- Alerts you to the presence of water where it shouldn’t be nearly instantly
- Can trigger the Moen Flo Smart Water Monitor & Shutoff to shut off your water supply if a leak is detected
- Also monitors ambient and temperature and humidity, and alerts you to readings outside user-defined ranges
- Connects directly to your Wi-Fi network, no hub required
Cons
- No provisions for integration in broader smart home systems
- Doesn’t support IFTTT, which would trigger other smart home devices
- Water-sensitive extension cables cost $20 each
- It's not a component of the Moen Smart Water Network
The Moen Smart Water Leak Detector is an excellent solution for alerting you to the presence of water in places it shouldn’t be. It’s a no-brainer buy if you already have or plan to install a Flo Smart Water Monitor & Shutoff valve, but it delivers plenty of value even if you don’t. The sensor can detect water through the contacts on its own body, and you can plug plug in an extension sensor attached to a 4-foot cable to monitor nearby areas of the floor. Our biggest criticism is that the sensor is not part of the Moen Smart Water Network and you’ll need a different app than to set it up.
Phyn Smart Water Sensor — Best smart water leak detector, runner-up
Pros
- Sends an immediate warning when water contacts it
- If you also own the pricey Phyn Plus, it can automatically turn off your main water supply to prevent catastrophic damage
- Industrial design prevents water ingress from the top of the device
- Operates on two AA batteries
- You don’t have to pay for the extension cable with remote sensing disk unless you need it
Cons
- Phyn makes the only compatible smart shut-off valve
- Can’t be integrated into a broader smart home ecosystem (including IFTTT)
- Operates only on 2.4GHz networks
- Will give you trouble if your dual-band Wi-Fi router uses the same SSID for both its 2.4- and 5GHz networks
If you own a Phyn Plus smart water valve, you absolutely should place one or more of these smart water sensor around your home. If the sensor detects water where it shouldn’t be, it can trigger the Phyn Plus to shut off your main water supply to prevent catastrophic water damage. On its own, it will give you plenty of warning of a localized water leak, so you can take immediate action. The Phyn Smart Water Sensor will also report the ambient temperature and the relative humidity at the location it’s placed, and it will warn you if either factor exceeds the tolerances you’ve set in the Phyn app.
Eve Water Guard (2nd Gen) — Best Matter compatible water leak sensor
Pros
- Easy setup
- Cable sensor can be stretched up to 490 feet with extensions
- HomeKit and Thread support
- Built-in siren and alert LED
Cons
- Wired design won’t work for everyone
- No Android, Alexa, or Google Assistant support
- Expensive
If you’ve gone all in with Apple’s HomeKit smart home ecosystem, there is no better solution than the second-gen Eve Water Guard. That goes double if you’re looking for Thread support and you think you’re planning to jump onto the recently ratified Matter smart home standard–backed by Amazon, Apple, Google, and Samsung SmartThings–that promises to finally unify the smart home market.
Flo by Moen Smart Water Shutoff — Best leak detector with automatic shut-off valve
Pros
- Monitors your home’s water supply line and can automatically shut it off to prevent water damage from leaks
- Reports on your home’s water consumption and detects water-use anomalies
- Measures the pressure in your water supply line and warns you if it becomes dangerously high
- Moen robocalls warn you of conditions that can prompt it to shut off your water for safety
Cons
- Moen’s algorithm isn’t super accurate at determining how much water your home’s fixtures and appliances are consuming
- You must use two different apps to operate both this smart valve and the Moen Smart Leak Detector
- Finicky about connecting to Wi-Fi (and limited to 2.4GHz networks)
- Unless you’re an advanced DIYer, you’ll want to hire a plumber for installation
- Not HomeKit compatible
As part of Moen’s home water network, the Flo Smart Water Monitor & Shutoff can protect your home from catastrophic water damage, save you money on your insurance and water bills, and help you use one of the Earth’s most precious resources more wisely.
Phyn Plus smart water assistant + shutoff (2nd Gen) — Best leak detector with automatic shut-off valve, runner-up
Pros
- Can prevent catastrophic water damage
- Can work in conjunction with optional stand-alone leak sensors
- Presents detailed analyses of your household water consumption
- Performs automatic daily inspections of your water supply lines
- Compatible with Amazon Alexa, Google Assistant, and IFTTT
Cons
- Best installed by a professional plumber
- Push notifications are easy to overlook
- Can be a pain to connect to your Wi-Fi network
- Not HomeKit compatible
The second-generation Phyn Plus is incrementally better than the first, but it’s also more expensive. That said, there is no better way to protect your home from catastrophic water damage caused by a plumbing failure, and you might qualify for a discount on your homeowners’ insurance policy if you install one. The Phyn Plus is pricey protection you hope you’ll never need, but catastrophic water damage will cost you many times as much. And even if you never experience a leak, this smart device will inform you of your household’s daily and monthly water consumption, so you can contemplate ways to reduce your use of this precious resource.
Flume 2 Smart Home Water Monitor — Best DIY whole-home leak detection system
Pros
- Tons of flexibility in slicing and dicing historical water usage
- Wide compatibility with most water meters
- Much better range and performance than the first-generation device
- Less expensive than water monitors that can shut off your water supply
Cons
- Installation can get messy
- Can’t automatically turn your water off to prevent water damage
- Can't pinpoint the source of a water leak
- Useless for homes without water meters (e.g., rural homes reliant on wells)
Unlike the Phyn Plus and Flo by Moen products it competes with, the Flume 2 cannot automatically shut off your water supply in the event of a catastrophic leak. The dual upsides to that is you can install the Flume 2 yourself, so can avoid the expense of a plumber, and this smart device is a whole lot less expensive than the more sophisticated competition. The Flume 2 will warn you a leak, so that you can take action, and it does report your water consumption. The company says its users have reduced their household water consumption by an average of 10 percent after installing the sensor. We like it a lot.
How we test smart leak detectors
To measure each sensor’s effectiveness, we placed it on a bathroom tile, and then poured enough water to cover the surface of that tile. Most sensors responded immediately, though we have noted a few exceptions.
We measured alarm volume using the Decibel 10th app on an iPhone, with the microphone pointed toward the sensor from six inches away.
We didn’t directly test integrations with other smart home devices, but inspected each companion app and the online service IFTTT for available features. We consulted manuals and product listings for battery life estimates and device dimensions.
Editors’ note: This testing methodology does not apply to leak detection systems that monitor your water supply line, such as the Flo by Moen, Sinopé Sedna, and Phyn Plus.
What to look for when shopping
You might be surprised by the diverse approaches to what seems like a simple task: detecting the presence of water where it shouldn’t be. Some operate on Wi-Fi, others require a hub to communicate. Some plug into an AC outlet, others require a battery. Some come with external sensor cables and mount to the wall, others lay on the floor. Most, but not all, have onboard sirens.
If the recommendations above don’t work for you, here are the specs and features you’ll want to consider when shopping for a smart home water leak detector.
Hub requirements: Some smart leak sensors that communicate using Zigbee or Z-Wave technology require a hub (e.g., an Aeotec SmartThings Hub) or a bridge to connect to your Wi-Fi network. Others can connect directly to your Wi-Fi network.
Connection protocols: If you own a hub already, you must make sure the sensor uses a compatible connection protocol. Fibaro, for instance, uses Z-Wave, which works with SmartThings. If you own a well-known hub, such as SmartThings, you’ll likely see its name on the sensor’s box.
Integrations: Some leak sensors allow you automate actions on other devices when a leak occurs. That way, you can trigger lights, turn on cameras, or sound an alarm. Devices that support IFTTT, a service that lets you automate tasks between connected devices and services, can trigger actions by third-party devices. Sensors that communicate with smart water valves, such as those from Phyn and Flo by Moen, can turn off your main water supply to stop a leak.
Size and extendability: Where do you plan to put your leak sensor? If it’s a tight space, make sure the sensor is either small enough to fit, or that it offers a sensor cable to extend its reach.
Built-in siren: Unless you plan to put the sensor far from where you might normally hear it, it’s helpful to have a siren onboard. That way, you’ll still get alerted at home even when the internet is down.
Additional onboard sensors: Some leak sensors can also measure other environmental conditions that can lead to problems at their extremes, such as temperature (a frozen pipe can burst and cause catastrophic water damage) and humidity (excess moisture in the air can allow mold to grow).
Power source: Most leak sensors are battery powered, but some, such as D-Link’s Wi-Fi Water Sensor, depend on AC power. An outlet-powered sensor with battery backup in the event of a blackout would be ideal; unfortunately, they are rare.
Editor’s note: Mel Nussbaum, the owner of Water Works Plumbing in Overland Park, Kansas, emailed this useful tip for preventing water damage due to frozen pipes bursting: “If you shut off your main water service valve [you’ll] never have the issue, and two minutes of your time [will] cost you nothing. By the time you’re alerted and get someone to take action you still will incur huge damages.”