Alarmed lock

An alarmed lock is a lock or a bolt with a small built-in siren that sounds when it detects blows, vibration or an attempt to force it.

It is usually locked and unlocked with an ordinary key and the alarm runs on batteries. The idea is that the noise catches the neighbours’ attention and puts off whoever is trying. There are also alarmed padlocks for metal shutters, storerooms or bicycles.

It should not be confused with an electronic or smart lock, which opens with a code, a card or a mobile phone. We do not install or repair those.

If you are interested in one, bear in mind that the alarm only works if the batteries are charged, and that the lock has to be good in its own right. To reinforce the door, cylinder and escutcheon, see security upgrades.