Different Types of Locks and How They Work

Different Types of Locks and How They Work

Residential and commercial properties in Perth are equipped with a wide variety of different types of locks, some of which are more suitable for certain applications than others. If you would like to learn a little about the most common types of locks that we deal with and what each type has to offer, we hope that this article will satisfy your curiosity. If, after reading it, you still have any questions about the various lock types in common use that you would like us to answer, please feel free to call or email us whenever you wish. We are always happy to assist new and existing customers in any way that we can and there is very little that our team of experts at Action Lock do not know about commercial and domestic locks in Perth and the surrounding area.

Your Quick Guide to Common Lock Types

Some of the locks in the following list are only fitted to certain types of windows or doors whilst others have various possible applications.

Single/Multi-PointMortice Screen Door Locks

Many of the cheaper screen doors on the market are fitted with simple latches that, while easy to operate, offer very little in the way of protection against intruders. However, if you invest in a high-quality security screen door, you can expect it to be fitted with a more substantial and effective type of lock. A common type of lock employed on such screen doors is the mortice lock. Screen door mortice locks are threaded: they are designed to screw into a fitting that is located inside of the screen door itself. This makes them inherently stronger than the type of locks that are simply screwed on to the side of a screen door and there are a couple more very good reasons that mortice locks are very popular in many countries across the globe, not just Australia. Firstly, they normally feature a latch and a keyhole, making them lockable from both the inside and the out. Secondly, they are available in many different sizes so they can be fitted to a wide variety of security screen doors.

Dead Bolts

This type of lock is commonly fitted to entrance doors on residential and commercial properties and differs from normal spring bolts in that the bolt can only be locked or unlocked by inserting a key that turns the cylinder inside, retracting the bolt. The best type of deadbolt to use in doors that contain breakable glass is a double cylinder deadbolt, i.e. a bolt that has to be locked and unlocked with a key from both the inside and the outside of the door. Single cylinder deadbolts can be used in solid wood or metal doors and feature a thumb piece that is used to unlock them from the inside. The solid metal cylinders inside deadbolts go through the door jamb and into a hole in the wall: a secure locking mechanism that can be very hard to force when properly installed in the right type of door. Many keyless locks – those that can be opened by entering a digital code or by swiping a card – also feature deadbolt cylinders.

Knob Locks

Often used as a secondary lock on entrance doors in residential properties, many people slip into the habit of using them as a primary lock due to the fact they are more convenient to open and close. Unfortunately, the simplicity of the locking mechanism in knob locks makes them very easy to circumvent. The lock cylinder in this type of lock is inside the knob itself, which means that all a determined intruder needs to do in order to force an entry is to break the knob off the door. They usually have a keyhole on the outside and a small piece on the inside that can be twisted to open the lock when grabbed between thumb and forefinger. Unless you would like to leave your house vulnerable to anybody equipped with a hammer, a wrench or a pair of heavy-duty pliers, you should never rely on a knob lock as your first line of defence in an exterior door.

Lever Handle Locks

This type of lock is most often employed on internal doors in commercial properties,  but they are sometimes also used on internal doors fitted in residential properties that are inhabited by elderly or disabled individuals. The reason they are favoured in such properties is because they are easy to open. Firm downward pressure applied to the large lever will open the lock from the inside, ensuring that whoever is inside can vacate the room they are in without any unnecessary delay in an emergency situation. One potential drawback of this type of lock is that they can be forced open by applying a great deal of pressure to the lever on the outside of the door, which means they may not be the best choice in commercial properties where security is a prime concern. However, a variation of the standard lever locks that feature a clutch lever is able to overcome this problem by allowing the lever to turn freely rather than turning the actual lock when strong force is applied to it.


This is the only type of commonly used lock that is not actually fixed to anything. Padlocks are used on gates and doors in both residential and commercial properties and their weakest point is often the part of the door or gate to which they are attached. If you purchase a padlock made of steel that cannot easily be cut with bolt cutters or sawn through with a hacksaw, make sure that you do not compromise its strength by attaching it to a handle or other part of your gate that is made of much softer metal.

If you would like impartial, professional advice on the best types of locks to fit in your property, please feel free to call and speak to one of our residential locksmiths during normal business hours