A Guide on How to Choose the Best Locks for Your Doors
Why Your Choice of Lock Matters
Your door locks are your first and most important line of defence against unauthorised entry. A high-quality, correctly installed lock can make the difference between a secure property and a vulnerable one. Equally, fitting the wrong lock type - or a poorly made one - can give a false sense of security without providing meaningful protection.
This guide will help you understand the main types of door locks and how to choose the right one for each door in your home.
Factors to Consider When Choosing a Door Lock
Purpose of the Door
External doors - front doors, back doors, side gates - require a much higher level of security than interior doors. For interior doors such as bedrooms, bathrooms, or storage rooms, convenience and privacy typically take priority over security strength.
Door Material and Construction
The material and thickness of your door affects which locks can be fitted. Wooden doors, metal doors, and uPVC doors each have different characteristics:
- Wooden doors suit mortice locks and cylinder deadbolts well
- uPVC doors are almost always fitted with euro cylinder locks and multi-point locking systems
- Metal and composite doors may require specialist hardware
Always check the manufacturer’s guidance and, if in doubt, ask a local locksmith.
Budget
Security should not be compromised for cost, but it is possible to find good-quality, certified locks at a range of price points. Spending a little more on your main entry locks is a sound investment.
Common Types of Door Locks
Deadbolts
Deadbolts are among the most secure options for external doors. They use a solid metal bolt that extends deep into the door frame, making them very resistant to forced entry. They come in two main variants:
- Single cylinder: key outside, thumb turn inside - the most common choice for residential front doors
- Double cylinder: key required on both sides - useful where there is glass near the door, but presents a fire safety consideration
Mortice Locks
Found in many older UK properties and commonly used in commercial buildings. Mortice locks are recessed into the door edge rather than surface-mounted, which makes them strong and resistant to tampering. They typically combine a latch and a deadbolt in a single unit.
Euro Cylinder Locks
The standard lock on most uPVC doors. The cylinder is a replaceable insert that controls the locking mechanism. Their main weakness is vulnerability to cylinder snapping - a common burglary technique. Always choose anti-snap cylinders for any external door.
Knob and Lever Handle Locks
Suitable only for interior doors. These locks can be defeated with basic tools and should never be used as the sole lock on an external door.
Security Ratings: What to Look For
BSI Standards
The British Standards Institution tests and certifies locks against recognised performance standards. For home insurance compliance and genuine security, look for:
- BS 3621 - the standard benchmark for deadlocks
- BS 8621 - for key-operated deadlocking night latches
- BS 10621 - for double-locking latches
Sold Secure Ratings
An independent testing scheme with three rating levels:
- Bronze - entry-level security
- Silver - medium security
- Gold - maximum tested resistance
For external doors in residential properties, aim for at least Silver, and ideally Gold on your main entry point.
Smart Locks: A Modern Option
Smart locks offer keyless entry via a smartphone app, PIN code, or fingerprint. They can be monitored remotely, set to allow temporary access, and integrated with other smart home devices. However, they should complement a quality mechanical lock rather than replace it entirely - most smart locks are not yet tested to the same standards as mechanical alternatives.
Lock Maintenance
Even the best lock will deteriorate without basic care:
- Apply a graphite-based or silicone lubricant to the keyway every six to twelve months
- Check screws and fixings for looseness annually
- Replace cylinders that show signs of wear before they fail
Get the Right Lock Fitted Properly
Choosing the right lock is only half the job - a poorly installed lock provides far less security than its ratings suggest. For expert lock change and installation services, speak to our team.