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Welcome to 'Security'- learn about the world of locks and Security

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Mortice Locks Support For this section

Security Locks There are many types of locks available, but how do you decide which is the best to use?  Insurance companies and the police recommend a five lever mortice deadlock which has the British Standard 3621:1980 kite mark stamped on it.  In fact, many insurance companies now insist that if you want them to insure you, you must have (in addition to other requirements) the British Standard rating on your locks.  But what does all this mean, and why is it an important security device compared to other locks. A British Standard deadlock must have the following: A minimum of five levers False Notching Handles must not operate the deadbolt The bolt must project no less than 14mm when locked Both sides of lock must be protected by anti drill plates Vulnerable fixing screws on all parts of the lock must be concealed when door is locked There must be at least 1000 key variations The mortice lock is a very popular type of lock and has been in existence for many years.  Chances are, you already have them fitted to your existing doors.  A mortice lock is the type of lock that has been designed to fit inside a door by means of a 'mortice'.  A mortice is simply a woodworking term that describes a hole that has been cut into timber as part of a woodworking joint.  The lock fits into a mortice that has been 'cut out' of the door edge, hence the term 'mortice lock'.  Other types of locks fit onto the door surface, these are known as rim locks, rim cylinder locks or night latches. If you pushed down one of the handles of an internal door, you will see that it operates what is known as a latch, which is the part that goes in and out on the door edge.  When the door is closed, this latch fits into a plate known as the 'striker plate' which is fixed into the door casing and serves to hold the door in the closed position.  The part of this latch that you see is only a small portion of it, in fact it extends beyond the position of the handles inside the door.  Because this latch fits inside the door, it is known as a mortice latch.     However, the type of mortice lock that would be fitted to your front door is different to what is fitted to an internal door.  To begin with, it is known as mortice lock, rather than a mortice latch, because it also locks the door in position rather than just holding it there.  This locking action is achieved by a bolt that shoots out of the lock when the key is turned and goes into the much larger and sturdier striker plate as shown here.  Once in this position, this locking bolt cannot be pushed back, in fact, the only way it can be retracted back into the lock, is by using the key again, so by unlocking it.  This feature where the bolt is fixed in position after turning the key is known as 'deadlocking'.  Hence the term mortice deadlock. Generally speaking, there are two types of mortice locks; the mortice deadlock and the mortice sashlock.  The mortice sashlock is pictured here, on the right. The mortice sashlock has incorporated in its design the facility for handles, so that in addition to having a locking bolt activated by a key, it also has a latch, which is operated by handles. The second type is known as the mortice deadlock.  The deadlock does not have the facility for any handles and works by key only, so that when fitted in position inside the door, you can only see a key hole or the plate that covers it, known as the escutcheon plate.  Both the sashlock and the deadlock are in fact deadlocks.     Continued on page: 2 Page top Doors and Security Back to Introduction Page 2