Automatic Water Shutoff Valves

Safety shutoff valves get smarter and smarter

broken water pipe in flooded room
Henrik Sorensen / Getty Images

Water damage in a home can be devastating to your property and your savings. The threat of water damage exists in every home, as long as it's hooked up to a water supply, because every water-using appliance, every fixture supply tube, and every pipe has the potential to leak. Once a leak starts, there's nothing to stop it because it is fed by the full city water pressure (or well pump, for homes with well water). If you're home when a leak occurs, you can use fixture shutoff valves or the house's main shutoff valve to stop the water flow. But what if you're not home, or you're asleep, or you simply fail to discover the leak until it's too late?

Enter the automatic water shutoff valve. This simple electric device can sense a water leak and automatically shut off the water flow to any pipe it is connected to. Many of these cost less than $200 and can save your house from a flood that can easily create $10,000 or more of damage in a matter of hours.

How Do Water Shutoff Valves Work?

An automatic water shutoff valve can control one or two appliance or fixture water supply lines, or it can control a home's main water supply. All it does is sense a water leak and shut off the water flow via an internal ball valve. It is triggered by a water sensor placed on the floor to detect water leaks near appliances that use water, like your refrigerator, ice machine, washing machine, toilet, dishwasher, or water heater.

The shutoff valve connects directly to the supply pipe or tubing, usually with a threaded compression-type fitting that does not require soldering and can be used with a variety of pipe or tubing materials. The valve unit includes a standard cord and plug for plugging into a wall outlet for power. Most systems these days include several sensors that connect to the valve unit wirelessly.

The sensors are placed on the floor, anywhere in the home where a leak may occur. If water ends up on the floor, triggering the sensor, a signal is sent to the valve, which shuts off the water flow completely. It then remains off until you turn it back on manually or by resetting the system. Some systems also include a low-temperature sensor that watches for freezing conditions in an unheated area, such as a basement or crawlspace. If the air gets cold enough to freeze (and potentially burst) pipes, the system automatically shuts off the water.

Which Type of Shutoff Valve Is Best?

Single-location shutoff valves are commonly used to protect the pipes or hoses serving the most likely places where leaks occur; namely, the washing machine, the water heater, and the toilet. Other supply lines that commonly leak include those for refrigerator/freezer water dispensers and ice makers, water filtration systems, and humidifiers, as well as any sink faucet or other plumbing fixture.

If you want to protect more than one appliance or fixture, it makes the most sense to install a whole-house shutoff valve. These are typically located near the existing main shutoff valve where the water supply pipe first comes into the house. The sensors can then be placed throughout the house to provide protection to all areas prone to leaks.