Some homeowners take it further, balancing a small cup or container on the handle inside.
If the door shifts, the object falls, creating an alerting noise. These aren’t alarms—they’re just clever ways to notice movement without spending a dime.
Of course, this is not a replacement for real security. Strong locks, reinforced doors, proper lighting, and cameras or alarm systems are still essential.
The foil trick is a quick, inexpensive way to stay alert—a mental nudge that adds a little extra peace of mind. Seconds to set up, nearly free, and surprisingly effective at keeping your home awareness sharp.
Have you ever tried a simple DIY tip that actually made a difference in your home? Share it in the comments and help others stay a step ahead!