If you’re reading this, you’re probably searching for a quick and easy way to replace the lock on a UPVC door, whether it’s for security, a recent move, or normal wear and tear. The good news is that most homeowners can replace a UPVC door lock on their own with a little help. It’s not as difficult as you would imagine.
Everything you need to know about changing UPVC door locks will be covered in this guide, including the tools you’ll need, the different kinds of locks, detailed instructions, and answers to frequently asked questions like how much it costs to change locks or how to change the combination on a combination lock, if you’re dealing with one.
Why You Might Want to Change Your UPVC Door Lock
There are several good reasons to consider changing UPVC door locks:
- You don’t know who has the keys to the new house you moved into.
- Your keys have been stolen or misplaced.
- Your lock is difficult to use because it is jammed or sticking.
- You wish to use a higher-security cylinder to improve the security of your house.
- You are converting to a combination lock system from a keyed lock.
Changing a door lock is a sensible method to improve home security and bring back peace of mind, regardless of the reason.
Understanding the Type of Lock on a UPVC Door
Euro cylinder locks are installed on the majority of UPVC doors. These locks are frequently found on contemporary front and back doors and are simple to repair. Make sure your door has this type of lock before you start. Your UPVC door probably employs a Euro cylinder if it has a multi-point locking mechanism.
The procedure is different if you’re dealing with a combination lock, which is commonly found on gates, barns, or cupboards. In a subsequent section, we’ll also discuss that.
Tools You’ll Need to Change a UPVC Door Lock
To successfully change locks on a UPVC door, you’ll need the following tools:
- A brand-new Euro cylinder lock that is the same size as the previous one
- A flathead or Philips screwdriver
- To measure the cylinder, use a measuring tape.
- Your current key (for taking out the old lock)
- A tiny screw-holding container
For increased security and insurance compliance, always get a British Standard 3-star anti-snap Euro cylinder.
Step-by-Step: How to Change Door Lock on UPVC Door

Step 1: Find the Retaining Screw by Opening the Door
Widen the door. A long screw that is approximately positioned in the center of the lock cylinder is visible on the door’s side, or edge. The holding screw is this one. Remove it with your screwdriver and place it in a secure location.
Step 2: Turn slightly after inserting the key.
Turn the old lock by 10 to 15 degrees in either direction after inserting the key. By doing this, the cam inside the lock will line up and make it easier to slide out. Ignoring this step will cause the cylinder to remain stationary.
Step 3: Take Out the Previous Lock
Pull the lock out of the door gently while holding the key in the turned position. It might come loose if you give it a little jiggle.
Measure the cylinder in step four.
Measure the cylinder from the middle screw hole to each end after the lock is removed. The majority of Euro locks are available in 40/40, 40/50, or 45/55 sizes. To guarantee that your new lock fits flawlessly, this is crucial.
Insert the new lock in step five.
After inserting the key, insert the new lock into the opening. To ensure the lock fits securely, turn the key a little bit once more to align the cam. The lock should easily slip into position after it is positioned.
Secure the retaining screw in step six.
After removing the long retaining screw, replace it and tighten it tightly. Avoid overtightening since this could harm the mechanism.
Step 7: Check the Lock
How to Change the Combination on a Combination Lock

Test the lock on both sides after closing the door. Make sure that the door locks firmly and the key turns smoothly. Make sure the screw is snug and the cam is positioned correctly if the mechanism feels stiff or doesn’t lock.
The procedure is slightly different if you’re dealing with a combination lock (such as those found on lockers, safes, or key lock boxes) rather than a Euro cylinder.
Here’s a brief tutorial on changing a lock’s combination:
Step 1: Open the Lock Using the Current Combination
If you don’t know the current code, unfortunately, you can’t reset it (unless it’s a model with a reset pin or button). You’ll need to contact the manufacturer or replace the lock.
Step 2: Locate the Reset Mechanism
Most modern combination locks will have a reset button or pinhole on the side or bottom. You may need a small tool like a pin or paperclip to activate it.
Step 3: Enter Your New Combination
While holding the reset button, set your new code by turning the dials. Release the button when you’re done, and make sure the dials are secure.
Step 4: Test the New Code
Make sure the new combination is saved accurately by testing it multiple times before locking it again.
These procedures will typically work for the majority of models if you’re wondering how to modify the combination on a combination lock. For optimal results, always follow the manufacturer’s recommendations.
What About Changing Window Locks?
Though not the main focus of this guide, changing window locks often goes hand in hand with changing door locks for complete home security.
To change a window lock:
- Identify the lock type (espagnolette, casement, sash, etc.)
- Remove the screws holding the old lock in place
- Install a new, matching lock
- Make sure it aligns properly with the frame catch
Upgrading or changing window locks is a smart move—especially on ground-level windows or areas easily accessible from the outside.
How Much to Change Locks?
If you’re wondering how much to change locks, the cost can vary depending on:
- The type of lock (Euro cylinder, mortise, smart lock, etc.)
- DIY vs. hiring a locksmith
- Brand and security rating
DIY Costs:
- Euro Cylinder: $20–$60
- Screwdriver Set: $10–$20 (if you don’t already have one)
Locksmith Costs:
- Standard door lock change: $80–$150 (excluding hardware)
- Emergency or out-of-hours service: Up to $250
Combination locks can be cheaper, depending on the type and where it’s used (padlocks or key safes).
Conclusion:
Knowing how to change the lock on a UPVC door is an important ability that any renter or homeowner should possess. It gives you peace of mind and gives you the ability to be in control of your own safety.
Whether you’re attempting to find out how to change the combination on a combination lock, replacing a broken lock, or upgrading to a high-security cylinder, the process is much less daunting than it may appear.
These easy upgrades, which range from replacing window locks to UPVC door locks, can significantly improve the safety and security of your house.