All You Need to Know About the Door Lock Changing Process

When Should You Change Your Door Locks?

Changing your door locks is one of the most straightforward ways to improve your home security. There are several situations where a lock change is not just advisable - it is essential.

After a Break-In or Security Concern

If there have been recent burglaries in your area, or if you have reason to doubt the integrity of your current locks, upgrading them immediately is the right move.

Lost or Stolen Keys

If your keys go missing, you must assume the worst: someone may have found them and knows where you live. Changing your locks straight away removes that risk entirely.

Moving Into a New Property

Previous owners, tradespeople, or letting agents may still hold copies of your keys. Always change the locks when you move into a new home or office - it is the single most important security step you can take.

Damaged or Worn-Out Locks

Locks that are stiff, corroded, or intermittently failing are a security liability. A lock that does not work reliably is almost as bad as no lock at all.

Upgrading to Smart Locks

Modern smart locks offer keyless entry, remote access control, and activity logs. If you are upgrading your home’s security technology, replacing older locks is a natural part of the process.

Types of Door Locks

Understanding the options available helps you choose the right lock for your needs.

Deadbolt Locks

A steel bolt slides into the door frame, creating a strong barrier against forced entry. Deadbolts are widely regarded as the most secure option for exterior doors.

Mortice Locks

Fitted inside the door itself, mortice locks combine a deadbolt and a latch. They are more secure than surface-mounted locks and are a requirement for many home insurance policies.

Euro Cylinder Locks

Cylindrical locks widely used in uPVC and composite doors across the UK. They are easy to replace but must be anti-snap rated - a critical feature that prevents a common burglary technique.

Smart Locks

Keyless entry systems controlled via smartphones, key codes, or biometrics. Smart locks offer convenience alongside strong security when paired with a quality cylinder.

Tools Required for Lock Changing

• Phillips and flat-head screwdrivers
• Tape measure
• Compatible replacement lock
• Drill and drill bits (for new installations)
• Chisel and hammer (for mortice locks)

Step-by-Step Door Lock Changing Process

1. Remove the old lock - Unscrew the lock mechanism from the door face and latch plate from the frame
2. Measure the lock dimensions - Note the backset (distance from the door edge to the centre of the cylinder) and overall length
3. Install the new latch or bolt - Insert into the door and secure with the provided screws
4. Fit the new lock body - Align with the latch and fix the escutcheon plates front and back
5. Test thoroughly - Check the lock operates smoothly from both sides before closing the door

Choosing the Right Door Lock

When selecting a replacement lock, consider:

• Security rating - Look for locks certified to BS 3621 or TS007 3-star for maximum insurance compliance
• Grade and durability - Higher-grade locks withstand more force and last longer
• Reputable brands - Established manufacturers such as Mul-T-Lock, Yale, and Ultion are well regarded in the UK

When to Hire a Professional Locksmith

DIY lock changing is manageable for straightforward cylinder replacements, but professional installation is recommended when:

• You are fitting a mortice lock for the first time
• The door or frame has damage that needs addressing
• You want to upgrade to a multi-point locking system
• You are unsure of the correct lock size or type

A professional locksmith will also ensure the lock is correctly aligned, which is critical for both security and longevity.

How Much Does Lock Changing Cost?

Costs vary depending on lock type and location, but as a general guide:

• Euro cylinder replacement: £50-£100 including parts
• Mortice lock replacement: £80-£150 including parts
• Smart lock installation: £100-£200 including parts

Always ask for a full quote before work begins.

Get Your Locks Changed by City Locksmith London

Whether you need a straightforward cylinder swap or a full security upgrade, City Locksmith London provides fast, reliable lock changing services across London.