Monday, May 22, 2017


This article aims to introduce and help you to identify the types of locks that are fitted in your home. Knowing your lock types can be helpful for several reasons. Firstly, if your lock needs fixing or replacing, it can be useful to know what lock type you require before contacting your local locksmith, as this will speed up the process. As well as this, often home insurance policies require you to know what type of locks are installed in your home.

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To begin identifying your door lock type, it can be helpful to:

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  • Look for a manufacturing stamp on the lock
  • Identify whether the lock sits on the outside (rim lock), or whether the lock is chiselled into the door (morticed lock)

Door Lock Types

Mortice Locks

Mortice locks are one of the most common types of lock fitted. They are most often used on front and wooden doors, but can also include sliding door locks and bathroom door locks. Mortice locks refer to locks that are fitted into the edge of the door, they are installed into a cutout in the door known as the mortice. There are different variants of mortice lock, including mortice deadlock and mortice sashlock. A mortice deadlock is usually used on front doors alongside a nightlatch.

With a mortice deadlock it is possible to lock the door from both the inside and outside, adding a greater level of security. Both sashlocks and deadlocks use a deadbolt to lock. However, mortice sashlocks do not require a key to lock and open the door, but it is recommended that a key is used to secure the property when it is vacant. With the sashlock variant, there are different security levels available, with 5 lever being the highest level of security.

Cylinder Locks

Cylinder locks are another type of lock that is commonly fitted on doors. There are different types of cylinder locks including rim locks and euro locks. Rim cylinders are always used with nightlatches. Cylinder locks consist of a hole that has an inner, smaller tube with pins. The lock works through the use of the pins which prevent movement unless the right key is used. Cylinder locks operate internally and externally. However, whilst they are easy to install, before fitting a cylinder lock, we encourage you to seek advice. This is because some variants of cylinder locks can be vulnerable to a technique known as lock snapping.

Rim Locks and nightlatches

Rim locks are locks that are fitted to the surface of a door. Rim locks include rim deadlocks, rim sashlocks and nightlatches. Nightlaches themselves have different variants, the main types being standard nightlatches and deadlocking nightlatches, the latter tend to be more secure. Nightlatches are fitted on external and front doors to secure them. They use a latch mechanism which works by allowing you to open the door as the spring withdraws into the casing, whilst the door can then be closed and secured by pushing it into the frame. A rim cylinder is then fitted to the outside of the door, attaching to the nightlatch through a hole in the door. By turning a key in the cylinder, the latch is operated thus allowing you to open the door from the outside.

If you have any questions or need help identifying or installing locks, then please feel to Contact us.