Generally doors are kept closed using a latch mechanism; this can be in the form of a simple tubular latch most commonly found on household internal doors up to a full size lock cased latch used on heavy commercial doors.
Dead Locking Mechanisms
To add extra security to a door the latch can be combined with a dead locking mechanism, which through the turn of a key throws a bolt to secure the door. This locking mechanism can be separate and the lock is then known as a dead lock, typically found on front doors. Alternatively it can be combined with the latch which is known as a sash lock, typically found on your back door.
The exceptions to this are bathroom locks which throw a bolt to provide privacy, usually by a simple turn mechanism. Night latches are where the latch is withdrawn using a turn or lever from inside and only by a key on the outside, generically known as Yale locks.
Multipoint Locks
Increasingly popular on household doors are multipoint locks or lift and lock systems. These generally throw up to five locking bolts at the same time and provide an added degree of security, when fitted with security cylinders.
To help make a property secure, insurance rated or approved locks are generally recommended along with additional bolts and surface locks which require a form of key to lock or unlock them.
