Whether a lock is described as a mortice lock or a rim lock depends on how it is mounted to your door and frame.

What is a mortice lock?

A mortice lock is one that is fitted inside the edge of the door. Mortice lock cylinders are inserted into a hollow, or ‘mortice’ in a door’s edge and a strike plate serves as the lining for a recess in the frame into which the bolt fits.

Mortice locks are difficult to force open as most of the lock mechanism is secured within the door frame. Some home insurance policies stipulate a home must use a mortice lock in order to meet compliance with the terms of cover. Mortice locks are also more aesthetically pleasing, as less of the locking mechanism is visible. Only the keyhole and faceplate are seen when the door is ajar.

What is a rim lock?

A rim lock is a lock that is mounted on the inside surface of a door. The lockbolt and key cylinder mechanism are contained within a lock mechanism fitted to the door itself, sometimes called the ‘nightlatch’. When in the ‘locked’ position, the lock bolt is caught in a keeper that is mounted on the inside surface of the door frame. This means rim locks are only suitable for inward-opening doors.

Since rim locks do less damage to the woodwork when fitting, they are often the lock of choice for heritage or listed properties.

Some rim locks can be unlocked using an electric release mechanism, which remotely releases the lock bolt from the externally mounted keeper. Our EL4000 Rim Deadbolt uses an electric release mechanism, making it suitable for use with flats or properties with shared access entry systems.