Locksmith warns against leaving keys in internal door locks

Locksmith Aleks, known as ‘El Serraller’, is warning against the common habit of leaving a key in the lock on the inside of a door for added security. He explains that for experienced burglars capable of manipulating cylinders, an internal key provides little to no obstacle.

Instead, the practice creates a significant risk for the residents themselves. In many standard cylinder locks, a key left on the inside blocks the mechanism, preventing anyone from unlocking the door from the outside with a duplicate key. This can lead to situations where homeowners are locked out of their own houses, necessitating expensive professional locksmith services to force entry.

To achieve genuine security, the expert recommends focusing on the quality of the locking system, such as high-quality security cylinders, protective rosettes, and multi-point locks. For those who require the convenience of leaving a key inside, he suggests using a double-sided cylinder mechanism, which allows the lock to function from both sides regardless of whether a key is inserted.