The Ultimate Guide to Choosing the Right Door Locks

When it comes to protecting your home and loved ones, the quality of your door locks is more important than you think! Interestingly, many homeowners don’t think about the quality or type of their door locks until they apply for home insurance.

If you have ever used a comparison site to find the best insurance deal, most sites and providers will ask specifically about the types of door locks fitted to external doors. Many people don’t realise the important role that door locks play in home security or how they can affect their insurance premiums.

You may be in the process of moving to a new home, where replacing your locks makes complete sense for security, but you may be completely unaware that it can also help you secure a better insurance deal. Or you may be looking to renew your home insurance and wondering if installing new locks can make your premiums more affordable—yes, they can!

Understanding the different types of door locks available is the first step towards making your property more secure and reducing the cost of your insurance policy. At Lockout247, we believe in helping homeowners with the knowledge they need to ensure their peace of mind. This guide will walk you through the main types of door locks in UK homes, their security levels, and when each is most appropriate.

Identifying Your Existing Door Locks

It is helpful to identify what locks you already have. Here are some simple ways to recognise common door lock types:

• Wooden Doors with Key Access on Both Sides: This often indicates a 5 Lever Mortice Deadlock. The lock mechanism is fitted inside the door, not on the surface. Look for the number of levers (ideally “5 LEVER”) stamped on the lock’s faceplate along the door’s leading edge.
• UPVC or Composite Doors with a Keyhole in the Handle or a Protective Surround (Escutcheon): These doors commonly feature a Euro Cylinder Lock which operates a Multipoint Locking System. You might need to lift the handle before you can engage the lock with the key, and you might see multiple bolt points engaging along the side of the door frame when locked.
• Wooden Doors with a Surface-Mounted Lock on the Inside and a Separate Key Cylinder on the Outside: This is likely a Rim Automatic Deadlatch, often called a Nightlatch or Yale Lock. These locks usually have a spring-loaded latch that automatically engages when the door closes. You will frequently find a mortice lock fitted below it for additional security.

Here, we examine these different lock types more closely, which can help if you are considering switching to a different type.

5 Lever Mortice Deadlock

Fitted within the thickness of wooden doors, this lock is operated by a key from both the inside and outside. It features five internal levers that must be aligned correctly by the key for the bolt to move.

Generally, these are more secure than three-lever mortice locks due to the increased number of levers, making key duplication more difficult. However, a standard five-lever mortice deadlock that does not conform to British Standard BS3621 may not have been tested against common burglary techniques.

This is a common choice for external front and back wooden doors and is often used with a night latch for enhanced security. It is more secure than lower lever mortice locks and can be keyed alike (using the same key for multiple locks).

5 Lever Mortice Deadlock Conforming to BS3621

It is similar in operation to a standard 5-lever mortice deadlock but meets the stringent requirements of British Standard BS3621. This means the lock has been independently tested against common attack methods like lock picking, drilling, and forced entry.

You can identify these locks by the British Standard Kitemark, the standard number (e.g., BS3621:2017) engraved on the faceplate, and the number of levers. Due to the independent testing and robust construction, these locks have significantly higher security than standard 5-lever mortice deadlocks, which are often a requirement for home insurance policies.

Key Operated Multipoint Locking System

Integrated into the frame of UPVC, composite, and sometimes timber or aluminium doors, this system features multiple locking points (bolts, hooks, or rollers) that engage simultaneously into the door frame when the key is turned. It is typically operated by a Euro Cylinder Lock.

This lock type offers high security due to the multiple locking points, making it significantly harder to force the door. It is the standard lock for UPVC and composite external doors commonly found on French and patio doors.

Euro Cylinder Lock

A cylindrical lock mechanism commonly used to operate multipoint locking systems on UPVC and composite doors, as well as some mortice locks on timber or aluminium doors. The keyway is a distinctive “euro profile” shape.

The security level varies significantly depending on the cylinder’s features. Basic cylinders can be vulnerable to lock snapping, bumping, drilling, and picking. High-security Euro cylinders incorporate features like anti-snap lines, anti-drill pins, and anti-pick mechanisms. Look for cylinders with a TS007 3-star rating for the highest level of security against snapping.

Rim Automatic Deadlatch (Nightlatch)

A surface-mounted lock fitted to the inside of the door, with a key cylinder on the outside. It features a spring-loaded latch that automatically locks when the door closes, requiring a key to open it from the outside. Often found on wooden and glass-panelled doors.

This lock offers a basic level of security but is typically used as a secondary lock in conjunction with a mortice deadlock for enhanced protection. It is also commonly used as an additional lock on external front and back wooden doors.

Why Choose Lockout247

At Lockout247, we understand the importance of secure and reliable door locks. We can provide expert advice on the best locking solutions for your property, whether you need a lock repair, lock installation, or a complete security upgrade.

We offer a comprehensive range of locksmith services, including emergency lockout service, 24-hour locksmith assistance, and the installation of high-security locks that meet British Standards. Contact us today for professional advice and reliable locksmith services you can trust. Investing in the right door locks is an investment in your safety and peace of mind.