A Mortice Locks is a lock that is inside the edge of a door so that it cannot be seen or removed when the door is closed, there are two types, Deadlock and Sashlock. A deadlock has only a locking bolt and a sash lock has a locking bolt and a latch that is operated by a handle and holds the door closed without the need of it being deadlocked i.e. a back door
A Night Latch is a door lock that can be operated from the inside by a knob and from the outside by a key. i.e. front door. Some night latched have a deadlocking facility as well, requiring a key on the inside.
These locks come in a variety of sizes and levels of security, one of the most popular and well know is the Chubb 5Lever British standard insurance approved mortice deadlock, a must for all wooden doors, which is usually accompanied with a Yale night latch.
A multi-point locking system has a minimum of three locking points that all lock
simultaneously by the turn of a key. Multi-point locks are most common on UPVC
There are over 450 different Multi point locking mechanisms on the market and they are available next day if required. The most common problem with multi point door mechanisms is that the door has dropped or the lock has become badly aligned, this puts excessive strain on the centre gear box which eventually gives up. These locks have an average life of 10 years. The additional locking points help[ to pull the door in tight and provide lots of locking points which are locked into place with Euro cylinder or oval key lock.
The main advantage of the Euro cylinder is that it can be easily changed without the need to change the whole locking mechanism, for example when a key is lost or a property changes hands. The lock can be operated from both sides and in some application the key will withdraw the latch in place of a handle, an example would be a front door could be easily opened using the handle from the inside but needs a key on the outside. Some locks are made with a thumb turn on the inside to allow locking and unlocking without a key in the case of a communal entrance or a fire exit. There are many different sizes available and it is very important to get the correct size, these locks have a weakness in that they can be easily snapped in half if the wrong size is fitted.