I primarily use the Ring app for notification on my smart-home activities. The doorbell camera alerts me when there is motion at my front-door and a camera in the garage alerts me to activity in the garage (such as when a neighbor/relative comes over to water the house plants). It is only natural to extend the Ring system to alert me to water leaks and other home conditions. The Ring Alarm comes with a keypad; I leave the keypad in the bedroom to get water leak voice alerts during the night when I have do-not-disturb setup on my phone.
Though the Ring Alarm system is based on Z-Wave wireless technology, it is a closed system. It is designed to handle 3 types of sensors–a flood/freeze sensor, a fire-CO alarm annunciator sensor and break-in sensors. For the first two, it announces the problem at the keypad but for a break-in, it sounds the siren. Since I use my Z-Wave system for dealing with water leaks, I integrate it with Ring via the flood/freeze sensor.
When the hub detects a leak, it commands the whole house water valve to close. I have added an external normally-closed (NC) magnetic switch to the leak sensor and a magnet to the valve lever arm. When the valve is open, the magnet is held in proximity to the magnetic switch and keeps it open. I selected a switch/magnet combination that has a reasonable sensing range. When the valve is closed, the magnet is moved away from the switch that then closes and signals a leak to the sensor. Doing a physical integration is extra work but uses standard interfaces to the Ring system making it more robust against changes to Ring. No matter what software changes Ring does, a short-circuit across the leak sensor terminals will be recognized as a water leak and the alarm will handle it accordingly.