An automatic water shut-off and notification system for interfacing with a water valve and an existing security system having a security system control panel and at least one water sensor connected wired or wirelessly on a zone of the security system control panel, the automatic water shut-off and notification system comprising a control module, the control module comprising: a trig input terminal configured for connection with an output terminal of the security system control panel; a valve control terminal and a valve power terminal configured for connection with the water valve; and a processor connected to the trig input terminal and the valve control and valve power terminals, the processor configured to act on a detection signal received at the trig input terminal indicating water detection by the at least one water sensor to activate the water valve.