Home security is not just about protecting our property against intrusion, it's also about protecting against other risks too, such as flood, fire, carbon monoxide leaks, and so on. So, it makes sense to extend our home security system to detect these other risks too.
You may choose to set up the system so that certain types of alerts only come to your phone as emails, rather than triggering all of the outside bells, lights, and whistles. This can be done by adapting the scripts in the next chapter so that they operate how you want them to.
There's nothing worse than being away for a few days and coming home to a flooded kitchen because a leak has developed under the sink. Our simple circuit will detect the presence of water and trigger an input on our home security system, which can then alert you. You can also buy kits and ready-built modules to do this, but the following circuit is cheap and features our opto-isolator as we're going to have a different...
