An In-Depth Guide to the Different Types of Locks and Their Uses

March 26, 2023

The oldest known pin-tumbler lock dates back to a palace in Ancient Egypt, nearly 2,700 years ago. As long as humankind has owned property, we have wanted to keep it safe and secure. Locks have come a long way since a Pharoah wanted to keep people out of his palace, and now we have many different types of locks to choose from.

But what is the best way to find a lock that works for you? Do you know your deadlock from a mortise lock?

Read our detailed guide below to learn about the many different lock types available and how they each better suit different purposes when it comes to securing your property.

1. Padlocks

Most people will recognize a padlock as one of the most common portable locks in existence. Padlocks are usually used in combination with a chain or latch to hold a gate, door, or box closed.

They have their origins in ancient history, with examples found in Roman and Greek archaeological digs. They have remained popular ever since due to their ease of use and transportability.

Padlocks come in all shapes and sizes , from tiny versions suitable for keeping a private journal closed to vast, sturdy versions that you would need bolt cutters to bypass.

Padlocks are not the most secure type of lock, and they can be easy to break and cut with the right tools. Some padlocks will come shrouded, which means the sides of the padlock extend upwards to cover the bar, making it very difficult to cut them open.

Padlocks come in two varieties, keyed and combination.

Combination padlocks have tumblers linked to a set code; usually, four numbers you can enter outside the lock. Turning the tumblers to the correct combination will open the lock and allow access. They are great if you are prone to forgetting your key, but can be quite easily cracked with a bit of know-how.

Keyed padlocks require a key to open. Some locks keep the key inside when opened, and will not release it until closed again. Some can also be rekeyed to match other keys on your key ring to make life a little easier.

2. Deadbolt Locks

These are the locks you find most commonly on external doors. They provide a good level of security and are more difficult to break or compromise, and you can only open with the correct key inserted and turned.

There are several types of deadbolt lock : Single, Double, C-Type, and the Jimmy-Proof or Vertical type. Each class provides an increased level of security.

The single type of deadbolt lock is a lock that requires a key on the outer side only. Internally, you can open the door without a key, and it just needs a doorknob or thumb turn lock. This makes leaving the property easier for both you and any potential intruder who has gained access from elsewhere.

Despite being the least secure model of the deadbolt locks, it is the most commonly found lock on front doors around the USA. It does provide the most accessible means of exiting a secured building in case of emergencies, such as a fire or gas leak. You will not need to find the key to leave the building in a hurry.

The double deadlock offers the same security as the single, except it requires a key on both sides of the lock. So, it provides additional protection, as the door can be secured from both sides, preventing intruders from an easy escape. However, it also means you can’t quickly open the door from the inside during an emergency.

Because of this fact, double deadbolts are banned in some areas, as they do not provide a safe, swift fire exit. If you do have a double deadbolt installed on your door, please ensure the key is in easy reach. Some people choose to leave the key attached via a cable not to be removed from the room where it is most needed.

A C-type deadbolt is a hybrid option between the single and double deadbolts. This means that when you are at home, you can leave your property secured by just a single deadbolt with quick access on a doorknob when you need to leave. However, if you go away for a prolonged length of time, such as on vacation, you can double deadbolt the door for extra security.

The final variety of deadbolts is the Jimmy-Proof or Vertical deadbolt. This deadbolt offers another layer of security, as it is mounted onto the surface of the door, and the design prevents it from being ‘jimmied’ open with tools.

3. Cylinder Locks

Cylinder-style locks are very popular and used for a variety of different functions, from door locks to cupboards. They are very commonly used for patio and yard doors. They can be very secure but come with different rating levels, so it is essential to check this before making a purchase.

Rim locks are a variety of cylinder lock, that used to be the most popular means of securing your house in the last century. The lock is installed onto the door and across the frame, and large or long key types often unlock them.

They are less secure than other locks, as the supporting screws can be bashed loose with enough force. If they are still used today, it is often with another lock, like a deadbolt, to offer additional security.

Mortise locks are another type of cylinder lock which are installed inside the door itself. The lock is then attached to the installed mortise device to create a secure lock. A mortise lock is only really visible from the edge of the door, so they are pretty easy to spot on an open door.

They come in different varieties, with varying numbers of levers, adding to the level of security. These levers will lock into different points of the door frame, top, middle, and bottom. The number of levers will increase how secure it is and how difficult it will be to break through the door.

Cam locks are the type of cylinder lock you will most often encounter in a filing cabinet, vending machine, or chest of drawers. A key usually operates them, and turning the key will also turn a piece of metal or ‘cam’ into place and lock the container.

You can also have keyless cam locks that require a unique handle to open them. Cam locks are not very secure and can be picked relatively quickly, and they are not suitable as secure door locks.

4. Lever Handle Locks

When it comes to internal doors, you often find them secured with a lever handle or knob locks. Offices, accessible toilets, and hospitals often employ these locks to secure their property.

As the name suggests, the lever handle operates by pushing a handle down to open the door. The key is inserted into the head of the handle to secure the lock on the door. You can install the handle in either direction, but the lock itself is susceptible to being forced.

Knob locks are spherical and look like an ordinary doorknob put with a lock in the center. Knob locks do get used as external door locks, often on rear entrances. However, they are very weak under force , and someone could pick them very easily. 

Do not use a knob lock as your primary entrance lock without some different kinds of door locks to back it up. It is not the most secure lock you can buy, and is better used for internal security instead.

5. Bolt Locks

The sliding bolt lock has been around since man first realized he could secure his property against intruders. It is a very simplistic system installed onto a door, or more likely, a gate, to prevent unauthorized opening.

Bolt locks are easily compromised when not secured by a padlock. If the bolt is within reach of the person on the other side of the gate, an issue can present itself. The smaller variety of this type of lock is often found on toilets in public places to give you a degree of privacy.

They are easily removed under enough force, but maybe enough to deter an opportunistic thief. They work well in combination with other types of locks to add additional security to a door.

6. Chain Locks

Chain locks are a type of bolt lock; however, they use a looser chain instead of a rigid bolt. This allows for the door to open slightly, yet remain secure. They are primarily used on front doors to provide additional security when answering the door to strangers.

If the chain bolt is in place, the door can only open as far as the length of the chain allows. Once the door is closed slightly, the tension on the chain will lift, allowing it to be slid out of the lock and the door to be opened fully.

A chain lock is an ideal solution for vulnerable people who feel unsure when to answer the door. However, they are only an additional form of security and should never be the primary lock on an external door.

7. Electronic Locks

Electronic locks have become a more popular solution in the last thirty years, especially as room door locks in hotels. They are a keyless solution that someone can reset very easily if something goes wrong, and can also track when someone enters a property.

Often electronic locks use keycards that either you need to swipe or insert into the door lock. Alternatively, they may require a passcode entered via a keypad.

Electronic locks work best in areas where lots of people require entry through a door. They are popular in workplaces due to the tracking feature, which allows logs to be kept of door access.

Electronic locks require a supply of electricity to open them, which may prove a problem during a power outage. However, some are battery-powered or have a backup supply so that you do not get locked in or out when the power goes out.

8. Smart Locks

Smart locks are the latest evolution in lock technology. They connect to the internet so that you can access them via a smartphone. Rather than using a key, you can use an application and unlock your home from anywhere in the world.

The standard smart lock usually runs on a Bluetooth system, which means that you have to be in the range of the door to unlock it. This makes it convenient for when you pull up to your door in the rain or cold and want to get inside quickly.

The wifi model obviously requires a wifi signal to be available at all times for the lock to work. With this model, you can unlock your door from work for a friend or family member if they need to access your home to help out.

Both types of locks can use a fingerprint or pin code. However, ideally, as with most online security, you should consider a two-step process to maximize the protection of the lock. Smart locks are usually battery-powered and can run down quickly, as both Bluetooth and Wi-Fi tend to drain a battery.

Smart locks are great for rental properties, as they allow your guests to access your property when needed, but you can change the password once they have left in preparation for the next guests.

Which Types of Locks Are Best?

Hopefully, this guide has given you a detailed explanation of the different types of locks you can use to secure your property. The traditional deadlock remains the most popular and most secure for external locks, and will provide you with a good quality of security.

If you would like to know more about installing secure locks on your property or further premises, please take a look at our list of services. We will be able to assist you in staying safe in and around your home.

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