Best water leak detectors in 2021

If you’re going on a much-needed vacation this summer, you should consider picking up one of the best water leak detectors before heading out of town. Installing one of these devices will let you know if you have a burst pipe or water heater, even if you’re thousands of miles away. Some will even help mitigate what could be a potential disaster. 

A water leak detector alerts you if it senses a leak from a pipe, dishwasher, water heater, or washing machine, so you can address the issue before your basement floods. Most water leak detectors cost less than $100 and can be installed by yourself, making them a very smart investment. 

Other, more expensive models can not only detect a leak, but can also shut off the water coming into your home. They can also monitor the flow of water through your pipes and recommend ways to conserve water — and lower your utility bill. These models cost upwards of $400 and needs to be professionally installed, but can be worth it in the long haul.

What are the best water leak detectors?

When choosing the best water leak detector, you first have to decide if you want a device that merely alerts you when there’s a leak, or one that can sense a leak and then automatically shut off the water to your home. The former generally costs less than $50, while the latter typically costs more than $400, and requires professional installation.

If you’re simply looking for something that can let you know if there’s a leak, then the best water leak detector is the Flo by Moen Water Leak Detector. It only costs about $50, and has two sensors as well as an alarm that sounds if water is detected. 

Plus, it can be linked to the best water leak detector that can also shut off your water: The Flo by Moen. This device is installed along your main water line, and has a flow rate sensor to determine your water pressure inside your house. Algorithms in the Flo can detect leaks based on the amount the pressure drops, and can automatically turn off the water in the event of a major leak. 

However, the Flo’s algorithms can also sense things such as a running toilet or a dripping faucet, so you can find out if you’re wasting water — and money elsewhere. In addition, you can get a certificate from Flo to give to your insurance company, which can help to lower your premiums. And, if you subscribe to Flo’s subscription service ($5/month), you get live monitoring and up to $5,000 in the event of water damage due to a ruptured pipe or water heater.

The best water leak detectors you can buy today

If you’re not ready to commit to a water-shutoff system, the Flo by Moen Smart Water Detector is a good place to start. This $49 device senses leaks, temperature, and humidity, and can emit an 85-decibel alarm when it detects water. It also connects to the Flo by Moen app, where you can link it with Alexa, Google Assistant, and other smart home systems.

This device comes with the main unit as well as a four-foot cable, so you can mount it on the wall, and not worry about it getting washed away if you get a flood. And, when you want to step up to a system that can also shut off your water, you can link it to the Flo by Moen shutoff valve.

The Flo by Moen monitors your water flow and can automatically shut off your water if it detects a major leak. In addition, the Flo checks your water pressure and temperature, and its app shows you how much water you’re using per day. It also tells you what’s using water, and it runs daily tests to determine if there’s a water leak. 

All users now get an Insurance Verification Letter, as well as the ability to see your water usage by fixture. If you opt for the FloProtect service ($5/month), you can get monitoring and live-chat support. FloProtect will also cover the cost of your deductible (up to $5,000) if there’s water damage. The company also increased the length of its warranty to three years.

Customers can purchase an optional battery backup ($249), which will provide up to three days of protection if power gets shut off.

Many pipes will burst when the water trapped inside them freezes and expands. That’s why, in addition to water leaks, this Resideo (a division of Honeywell) sensor can also detect temperature changes and humidity, and send you an alert when things get too cold. The Lyric sensor runs on two AA batteries, which are rated to last up to three years. It includes a 4-foot cable, the entire length of which can detect leaks.

When the Lyric Freeze detects a leak, it sends an alert to your phone and emits a 100-dB alarm. It also connects directly to your Wi-Fi — no hub needed. Resideo’s  products also work with a wide range of smart-home systems.

Not only can the Phyn Plus Smart Water Assistant alert you if there’s a leak, but it can also automatically shut off the water coming into your home, which is why it’s the best water leak detector with a shutoff valve. 

Phyn’s super-smart water assistant has a series of blue LEDs along one edge that give the illusion of flowing water. Inside the device is a water-flow sensor, as well as some interesting algorithms that can detect leaks throughout your house based on water pressure. It can even tell the difference between a toilet flushing and a drip from a faucet, and give you insights into how much water you’re using. So, you don’t need to install remote sensors throughout your house. 

The Phyn Plus can be installed indoors or outdoors, and works with Alexa, Google Assistant and IFTTT. Unlike the Flo by Moen, there are no additional subscription fees. However, it has to be plugged in to work, and there’s no battery backup.

For those whom the Phyn Plus Smart Water Assistant + Shutoff valve is too expensive, the Phyn Smart Water Assistant could be the answer. This device, which costs less than half the price, does everything the Phyn Plus does, except for having an automatic shutoff valve. 

Like the Phyn Plus, the Phyn senses the water pressure in your home, can detect when there’s a drop in pressure and using algorithms, can let you know if it’s being caused by a burst pipe or just a leaky toilet. Because it doesn’t include a shutoff valve, the Phyn can be easily installed by a homeowner, under any sink. The one caveat is that you’ll also need a power source nearby. But, the Phyn could save you money over the long haul, even if you don’t have a major catastrophe.

Unlike other water shutoff valves, which require a plumber to install, the Guardian Leak Protection Kit sits on your water line and turns the shutoff handle already on your line. That means you don’t need to call in a plumber to cut your water line and install it. It’s compatible with quarter-turn metal ball valves from 0.5 to 1 inches in size.

The Guardian comes with three wireless water sensors, which you place in the areas that are most likely to leak, such as under your sink or by your water heater (they have a 1,000-foot range). Additional sensors are $49 each. It also performs periodic tests to ensure the device is in working order, and an optional battery backup ($29) will keep it running for 12 hours if your power goes out. Unlike the Flo and Phyn devices, though, it doesn’t monitor water usage, and it doesn’t work with any other smart-home systems.

Leaksmart makes several smart water shut off valves. Its least expensive is the cut-in water valve detection kit. However, it requires a plumber to install, which negates the cost savings. The Leaksmart connects wirelessly to remote water detectors (one is included with the kit; additional sensors cost $69). 

The Leaksmart valve connects via Zigbee to a Leaksmart Hub (included in the starter kit), which allows you to monitor and control the valve remotely from your smartphone. Leaksmart’s third-generation hub also integrates with Google Nest, Wink, Google Assistant, Amazon Alexa, Control 4 and SmartThings.

While you can purchase the Leaksmart through online retailers, the company recommends you purchase it through a licensed plumber. Leaksmart also makes a Snap-on Valve Controller, which doesn’t require you to cut into your water pipe. However, it’s only available as a kit for $795.

What to look for when buying a water leak detector

Water leak detectors fall generally into two categories: those which can shut off your water, and those that can’t. The latter are generally inexpensive — less than $100 — and will send an alert to your smartphone when they sense water. However, it’s then up to you to turn off your water, which can be a problem if you’re not at home. Those that have shutoff controls typically cost upward of $400 and require a plumber to install, but could be worth the investment, as they’ll not only help reduce catastrophic damage, but can also help lower your monthly insurance bill.

Regardless of the type of water leak detector you purchase, here are a few things you need to consider before you buy.

• Battery or plug-in? Some leak detectors run on batteries, while others need to be plugged in; the former type makes it easier for the detectors to fit into locations that are far from an outlet, but their batteries will need to be replaced every year or so.
• Built-in alarm: A detector with a built-in alarm will sound a siren, so that you can hear where the leak is coming from, without your smartphone.
• Smart-home integration: While not a necessity, if a detector works with other smart- home systems, such as Alexa or Google Home, you can have a light flash in your house, for instance, when there’s a water leak.