Door Lock Types – A Simple Guide for your Home (with Pictures)

You may want to know what door locks you have on your front & back doors, our guide will help you find out what type of door locks you have fitted in your home.

When getting house insurance most comparison sites or providers will ask what type of door locks are on your front door & all external doors.

Find out below how to tell what type of door lock you have with some simple ways to tell, plus the advantages & disadvantages of each door lock type.

Types of Door Locks for Homes

To help you identify if you have a deadlatch, mortice deadlock or a key operated multipoint locking system, we will tell you about the following main types of house lock.

5 Lever Mortice Deadlock  |  BS3621 5 Lever Mortice Deadlock  | 
Key Operated Multipoint Locking System  | Rim Automatic Deadlatch  |  Euro Cylinder Lock

The first lock we will look at is a five-lever mortice deadlock, which is a lock that seems to confuse a lot of people.

1. 5 Lever Mortice Deadlock

Type of Front Door Lock & Back Door Lock

A 5 lever mortice deadlock is commonly fitted to wooden doors and is locked from both the inside and outside with a key, they are fitted within the material of the door, rather than on the surface.

Any five-lever mortice deadlock that is NOT BS3621 approved will usually have a Nightlatch fitted as additional security. We recommend any Nightlatch fitted as a 2nd lock is a British Standard Approved Nightlatch.

What a 5 Lever Mortice Deadlock looks like

How secure is a 5 Lever Mortice lock?

A standard 5 lever mortice deadlock won’t be as secure as a mortice deadlock conforming to BS3621 though, for example usually, there will be no hard plates to protect against drilling.

How to Tell If I Have a 5 Lever Mortice Deadlock?

The first thing you should know is that a 5 lever Mortice Deadlock is NOT found on uPVC & composite doors, look out for the below:

1. Wooden Door – You will have a Wooden/Timber door
2. Open With a key – You can open the lock from both sides with a key
3. Lock Fitted in Door Material  – The lock is fitted into the leading edge of the door NOT the surface of the door
4. 5 Levers – The number of levers SHOULD be stamped on the faceplate of lock e.g “5 LEVER”

Number of 5 Levers stamped on Faceplate of Lock

What is the difference between a 3 lever and 5 lever lock?

The difference between a 3 lever lock and a 5 lever lock is that a 3 lever lock is less secure because it has fewer levers which increases the risk of key duplication.  Also, a 3 lever lock will NOT be BS3621 approved due to the poor security of the lock.

What is the difference between mortice deadlock and sash lock?

The difference between a mortice deadlock and sash lock is that a mortice sashlock has a latch and bolt to open and close the lock.  Where-as a mortice deadlock does not have a latch to open the lock.

Door Type Commonly Fitted To

A 5 lever Mortice deadlock is found on the following door types:

• External Front door – very common
• External Back door – very common
• Internal doors – not as commonly used

Advantages

The pros of having a 5 Lever Mortice deadlock as your door lock are:

1. More secure than having a 3 lever deadlock
2. Can be keyed alike

Disadvantages

The cons of a 5 Lever Mortice deadlock are:

1. A mortice deadlock NOT conforming to BS3621 means the lock may only be tested by the manufacturer
2. May not be tested against burglar techniques

What is the best 5 Lever Mortice lock?

The best & most secure 5 Mortice lock is a lock that is Kitemarked to British Standard BS-3621.  A Kitemarked British Standard lock ensures the mortice lock has been tested against burglary techniques such as drilling.

For more on BS3621 & British Standard locks click here.

How much does a 5 Lever Mortice Deadlock Cost?

The price of a 5 lever mortice deadlock is from £26, the price will vary dependant on the standard of mortice lock fitted and brand of door lock.   A 5 lever mortice deadlock will be slightly more expensive than a 3 lever lock.

For prices of door lock types see our locksmith price list here.

2. 5 Lever Mortice Deadlock Conforming to BS3621

More Secure Type of Front Door Lock & Back Door Lock

A 5 lever mortice deadlock conforming to BS3621 will have the British Standard Kitemark engraved on the faceplate of the lock and operates the same way as a Standard 5 lever mortice deadlock.

Difference Compared to a Standard 5 Lever Mortice Deadlock

More Secure – the difference compared to a standard 5 lever mortice deadlock is that a BS3621 approved 5 lever mortice deadlock is more secure and is tested against common theft methods.

How to tell a 5 Lever Mortice Deadlock conforms to BS3621

The quickest way to identify that your Mortice Deadlock is approved to BS3621 is looking for the following:

1. Kitemark Engraved – The Mortice Lock will have the British Standard Kitemark engraved on faceplate
2. Number of Levers Engraved –  Faceplate should state the number of levers the lock has
3. Standard Number Engraved – The Faceplate of the lock will state the standard number e.g BS3621:2017

For more info about BS3621 locks read our guide here.

Door Type Commonly Fitted To

A 5 Lever Mortice Deadlock approved to BS3621 is found on the following door types:

• External Front door – very common
• External Back door – very common
• Internal doors – not as common as front doors.

Advantages

The pros of having a 5 lever Mortice Deadlock conforming to BS3621 are:

1. Tested against common burglar techniques such as lock picking and drilling.

How much does a BS3621 5 Lever Mortice Deadlock Cost?

The price of a BS-3621 5 lever mortice deadlock will be from £36. 

For prices see our locksmith price list here which has costs of locks & estimated locksmith charges for different types of locksmith work.

What are popular brands of BS3621 Mortice Dead Locks?

The most well-known manufacturers of BS3621 Mortice Dead Locks in the UK are as follows:

• ERA
• Union
• Yale
• ASEC
• Chubb
• Legge

3. Key Operated Multipoint Locking System

Type of Front Door Lock & Back Door Lock

A key operated multi-point locking system is fitted into the body of the door and locks into the door frame.

This type of door lock is commonly found on upvc front and back doors, plus uPVC patio doors.  You will also find mult point locking systems on composite and timber doors.

When the lock is engaged multiple bolts will engage into the door frame, usually with a minimum of 3 points and sometimes 4 or 5 points, which adds a higher level of security. The mechanism is usually operated with a euro cylinder lock to which the key inserts.

What a Key operated multipoint lock looks like

How to Tell If I Have a Multpoint Locking System?

You can tell your door lock type is a multpoint locking system:

1. If your door is made of uPVC or composite, most likely you’ll have a multipoint locking system
2. Do you have to lift your door handle to then use the key to lock the door?
3. When looking at the side of the door, do multiple hooks stick out when lifting your handle?

Types of Doors

• Key operated multipoint locks are mostly found on UPVC and composite entrance doors, but can also be found on French and Patio door types.
• Usually fitted to UPVC and composite doors, but can also be fitted to timber and Aluminium doors.

Door Type Commonly Fitted To

A key operated multipoint lock is found on the following doors:

• External Front door – very common
• External Back door – very common

Advantages

The pros of having a multipoint locking system as your door lock are:

1. More locking points so it’s harder to force the door.
2. Only one cylinder is required to lock the full mechanism and can be keyed alike with other cylinder locks so fewer keys needed for one property
3. Easy to change the cylinder or upgrade to a better standard cylinder.

Disadvantages

The disadvantages of a multipoint locking system are:

1. If you don’t know how to operate the locking system you may not fully lock the door properly.
2. The most common entrance type acts as a night latch when closed and allows for easy exit when the property is occupied, but it is important to lift the handle and double lock the mechanism before retiring to bed or when leaving the property.
3. However, be aware there are a few other methods of double locking these types of locks and you should acquaint yourself with the proper method.

Multi-Point Locks Only have One Lock Cylinder

You only have one lock cylinder, although this is convenient it’s fewer locks to defeat (a traditional wooden door may have 2 or more different locks on it).

Therefore it is essential that the cylinder has been tested to SS312 Diamond Approved or TS 007 3 star kitemark standard against Picking, Drilling, Bumping and Snapping.

Alternatively, you can have a minimum of 1-star cylinder with 2 star PAS24 handles fitted.

SS312 Diamond Euro cylinder fitted on Multipoint locking system | Image by Mul-T-Lock 

When used in Multi Occupancy Properties
On properties with multiple occupancies, ie.a block of flats or a house converted into flats, a thumb turn cylinder must be fitted for easy egress in case of emergency.

Expert Tip
Remember if your locking system does not lock properly, your insurance may not cover for your losses.

Burglars wander around streets and gardens during the night trying door handles, because they know most people do not lock the doors correctly.

uPVC Door Security Tips
What is the Best uPVC Door Handle?

4. Rim Automatic Deadlatch with Key-Locking Handle

Type of Front Door Lock & Back Door Lock

A rim automatic deadlatch (nightlatch) is fitted on the inside of your door, with the key locking cylinder to insert your key to open the door located on the outside of the door.

You will find Deadlatches commonly referred to as Nightlatches and Yale Locks as well.

• Locked and unlocked from both sides with a key inserted in a rim cylinder.
• Will NOT be the only lock on your door
• A mortice lock is commonly fitted alongside a nightlatch

How to Tell If I Have a Rim Automatic Deadlatch?

If you have a rim automatic deadlatch fitted there are some signs below:

1. Often found on wooden doors
2. You might have another lock fitted lower down on your door, usually a mortice deadlock
3. The lock is surfaced mounted, rather than morticed into the door
4. When you close the door, you need a key to back in

Types Of Doors

Deadlatches (Nightlatches) are found on wooden/timber doors and also glass panelled doors.

Door Type Commonly Fitted To

You will find a deadlatch (nightlatch) found on the below types of doors:

• External Front Door – very common in homes
• External Back door – very common in homes

Advantages

The advantages of having a deadlatch (nightlatch) as your door lock are:

1. Easy to use
2. Locks automatically once shutting

Disadvantages

The disadvantages of using a deadlatch as your main door lock are:

1. Unless you fit a BS 3621-night latch, will require an additional lock fitted to your door to improve security, such as a mortice lock.

Difference Between Rim Locks and Mortice Locks

The difference between a Rim lock and a Mortice Lock is that a rim lock is fitted on the surface of the door, whilst a Mortice lock is fitted in the door edge.

Expert Tip
Fitting a Night Latch that is British Standard approved will improve the security of your door.

Nightlatch Guide (Best & Most Secure)

5. Euro Cylinder Lock

Type of Front Door Lock/Back Door Lock & Sometimes Internal Doors

A euro cylinder lock is commonly fitted to uPVC & composite doors and is used with multi-point locking systems and are also fitted to some mortice deadlocks and sashlocks on timber or Aluminium doors

Euro cylinders are now one of the most common types of locks fitted to modern homes.

How to Tell If I Have a Euro Lock Cylinder?

You can tell your door lock type is a euro cylinder lock with the below signs:

1. If your door is made of uPVC or composite most likely you will have a euro cylinder lock fitted
2. The lock that the key is inserted into looks like the pictures above
3. The lock is found fitted in a handle or escutcheon (protective surround)

Door Type Commonly Fitted To

A euro cylinder lock is found on the below door types:

• External Front door – very common for homes
• External Back door – very common for homes
• Internal doors – not as commonly used as internal locks in homes, but can be used in offices, schools, hospitals.

Advantages

The advantages of having a euro cylinder as your door lock are:

1. When fitted to the correct lock standard will help to prevent lock snapping, drilling, lock bumping or picking
2. Easy to operate
3. Easily changed to upgrade to a higher standard of security
4. Can be keyed alike or master keyed so fewer keys are required to a property

Disadvantages

The only disadvantage of a euro cylinder lock on your door is:

1. If the incorrect security standard is fitted, the lock will be at risk to lock snapping & other forms of attack

Expert Tip
Make sure you fit a Euro cylinder lock that is either SS312 diamond approved or TS007 3 Star.

Most Secure Euro Cylinder Lock

Frequently Asked Questions

1. What is the best type of front door lock?

The best type of front door lock depends on a few factors such as the type of door and also the building type.

Door Type – A Wooden door will require a different lock compared to a uPVC or Composite door, as most wooden doors have TWO locks fitted.

Building Type – A door lock on a flat or apartment (or a dwelling with a single exit) will have different escape requirements compared to a domestic house lock.

This is a reason why a vetted, inspected and competent locksmith should be specifying and fitting your door locks.

We also recommend your door lock is independently tested (e.g British Standard) with the correct egress requirements followed. To read our guide on British Standard Locks click here.

2. What brand door lock is the best?

The brand of lock you choose is a personal choice, we recommend any lock has been Independently tested meaning a lock has met minimum security and durability needs.

3. Do I need two locks on front door?

Two locks are commonly only found on Wooden Doors.

4. What is the best lock for a Wooden Door?

The best lock for a wooden door is a lock that meets the requirement of BS3621, the type of lock fitted can be a night latch, mortice deadlock or mortice sash lock.

A non-tested night latch can be used for access but it must be supported with a tested lock so you would have two locks on the door.

It should be noted that if a non-tested night latch is used on its own, the door is not securely locked and is in just a latched state and vulnerable to attack.

Live in a flat or apartment?  If the door is on a single exit dwelling (flat or apartment) then the lock should meet the requirement of BS 8621.

5. What type of lock is on a uPVC Door?

You will usually find a multipoint lock with a Euro cylinder on most uPVC doors.

Euro Cylinder locks are prone to lock snapping though, please read our guide here on lock snapping.

The For extra security, we recommend the lock standard of any euro cylinder on a uPVC door is either an SS312 Diamond Approved Cylinder or TS007 3 Star.

6. What is the best lock for a Composite Door?

If your composite door has been tested to PAS 24 and carries a Secure by Design certificate, then the lock has been tested to a very high level of attack so new locks are not needed.

If the door is untested then changing the lock cylinder to a Sold Secure SS312 Diamond cylinder or TS 007 3 star cylinder will prevent locks being broken and burglars gaining entry.

7. How Much does a Door Lock Cost?

Please read our locksmith price guide here which covers the price of locks and even a checklist of questions to ask a locksmith if you are looking to change your locks.

8. What does Police Approved Door Lock mean?

A police approved door lock means your lock has been tested to Secured by Design requirements.

Security products that meet Secured By Design requirements are then awarded the ‘Police Preferred Specification’ status which is often referred to as Police Approved.

Check your door lock is “Police Approved” here

Help I’m Still Confused

If you are still confused about the type of door locks you have fitted, we recommend contacting your nearest locksmith approved by the MLA who will be able to help.

Or you want to upgrade your door locks to comply with BS3621 again a locksmith approved by the Master Locksmiths Association can help.

Further Reading

• Locksmith Price List – our price guide also has a checklist of questions.
• Best & Most Secure uPVC Door Handles