Few home issues will ruin a day like a water leak. Water damage is not only inconvenient but can be very costly to remediate after the event. I once had a bad experience flooding the 2nd floor of an apartment, and ever since, I’ve been extra sensitive to water damage.

Managing Leaks

When I recently moved into a new house, leak mitigation was near the top of the list of risks to monitor and automate. Although leak mitigation may sound like a fancy, expensive solution, it’s surprisingly accessible with a solution available for under $100 using a wirelessly controlled motor and Home Assistant. There are two aspects to leak mitigation: monitoring for abnormal conditions, and the ability to automatically mitigate the leak.

I chose Xiaomi’s leak sensors along with a handful of SimpliSafe leak sensors running on a separate system. I’ve written previously about integrating inexpensive sensors like the ones Xioami makes using DeCONZ and Conbee II. These sensors are placed throughout the house near likely leak locations such as sinks, hot water tanks, and the laundry room. Home Assistant acts as a state machine, constantly polling or receiving updates from water sensors throughout the house. Whenever a wet condition is detected, a Node-RED automation fires to close off the water main to the house.

Leak Mitigation Isn’t Fail-Proof…

First, the drawbacks. If a leak occurs in a location not monitored, this automation won’t be much help unless someone is physically present to shut off the water main and drain sinks, toilets, etc.. If the power is out or the network is impaired, and connectivity to either a sensor or the shut-off motor fails, then it’s also a risk.
Those are the main risks present with this system.

…but it’s close

Now for the benefits.
First, peace of mind when I’m away. I already have a vacation mode to manage climate and simulate activity within the home when I’m away, but this adds an additional layer of control. Vacation mode is a context that automatically occurs when duration and distance thresholds are exceeded. I’ve integrated water shut-off as another action that fires whenever vacation mode is invoked to mitigate the risk of a leak occurring outside the sensor range.
Second, the cost of installation – including parts and time spent installing – is negligible.

In the age of Google’s “helpful home” and a general transition away from “smart home” to a seamless home that helps you by solving problems, this is one of my favorite integrations to date. I went with a Z-Wave product made by Dome, but there are plenty of similar shut-off motors on different standards such as Wi-Fi or Zigbee.

Dome Shut-off Valve
Installation is straightforward and involves lining up the motor and mounting it near the water main shut-off valve. It doesn’t have to be the main water shut-off valve, and the Dome shut-off can be installed on pretty much any ball valve. Other areas that could be managed include hot-water tanks, pool control systems, and so on.

Home Assistant is incredible, free, and open-source

This was my first foray into Z-Wave, as I prefer Zigbee due to the support of larger networks. I continue to be blown away by the ease Home Assistant’s integration with a wide range of collections and vendors. Z-Wave took me a few minutes to set up, mainly due to integrating the physical Z-Wave controller with my Docker setup.

I had a spare Nortek HUSBZB-1 stick (bottom-right), which I placed a few feet away from my Conbee II Zigbee controller (upper-left). My concern about the wireless interface was unfounded as the signal strength was strong between the controller in my office and the Dome motor’s placement in the basement.

zigbee and z-wave radio controllers

Once paired, I tested a few times to ensure the lever was shut entirely and completely opened in both states. It’s controllable from Home Assistant’s UI or from an assistant like Google Home or Alexa.

Dome Water Shut-off

Super easy leak mitigation with Dome and Home Assistant

I continue to be impressed by Home Assistant. At the time of this post, Home Assistant is in the top 20 most popular open-source Github projects.

Shut-off Control

You can learn more about Home Assistant here or check out Dome’s website here.