Water leaks and water damage are one of my biggest fears as a homeowner. With hardwood floors throughout my house, even a small water leak could turn into a massive repair bill and a huge inconvenience to get them repaired. A slow drip from a sink can quickly cause thousands of dollars (or tens of thousands) in damage to your floors and cabinets. If I had to choose one smart home category that actually gives me peace of mind, it would be the ones that prevent disasters. In 2026, the water leak sensor is still the most critical piece of hardware in my HomeKit setup.