Locks are the first line of defense against intruders. No locking mechanism is burglar proof, but good locks can be an effective deterrent.
Primary locks are referred to as key-in-knob locks or cylindrical locks. These locks provide minimum security and are popular, as they are low cost and simple to install. There are two styles of key-in-knob locks available. The first is the spring latch which requires no key and has a beveled edge bolt that can simply be cheated by inserting a piece of plastic card or metal between the door and frame. The second is the dead latch bolt which operates the same way as the spring latch, but has a dead-latch plunger that when engaged makes the latch inoperable.
Auxiliary locks refer to secondary locking mechanisms that should be installed with the primary lock to provide more adequate security. Examples of auxiliary lock systems area as follows:
DEADBOLTS: The term deadbolt describes the exact function of the mechanism. The bolt is ‘dead’; that is to say the bolt cannot be slipped with a card or tool, but can only be disengaged with a key. The minimum throw of a deadbolt should be 1”. The surrounding collar of the deadbolt should be made of good quality material so that it can not be crushed or have a slip ring that is separate from the deadbolt mechanism and can rotate freely to prevent crushing or twisting. The strike plate should be installed properly with long screws that anchor in to the frame, which increases the security benefit of this locking mechanism. Deadbolts provide good to excellent security depending on the quality.