Home Improvement

uPVC Door Lock Mechanism Broken? Here’s What to Do!

Is your uPVC door lock mechanism broken? Then you’ve come to the right place. This post is about dealing with this problem and we explain in detail:

  • how to choose a suitable lock,
  • what some common lock problems are,
  • how to replace it, and
  • how much it may cost you.
Table of Contents:

What’s the Lock Type of Your uPVC Door?

Contrary to popular belief, not all lock types are suitable for all types of doors. UPVC doors require a special type of lock and you need to know exactly what type your door has so you can get the right replacement. For uPVC doors, multipoint locks are used. That being said, there are different types of multipoint locks.  

What is a multipoint lock? If you open your door, you’ll see a long metal strip which bolts into the side of the door. It has multiple points, all of which lock the door, hence its name. You can distinguish the types by looking at their locking point. So, that’s how multipoint locks work. 

Multipoint locks have one lock cylinder, which may be convenient for you, but it makes it a bit easier for problems with it to occur. Common problems with uPVC door locks are fairly easy to fix but some require the help from a professional. 

You may also like:
Home Security and Safety Tips
Different Types of Door Locks – a Fantastic Guide (+ Illustrations)

UPVC Door Locking Mechanism Problems

Lock mechanisms see a lot of usage, which makes them prone to various problems. UPVC door lock problems can differ and can also be caused by weather conditions, improper usage or they simply weaken with time. 

Of course, if you hit, kick or slam it hard, the lock is likely to break beyond repair and you’ll need a brand new one. But if that’s not the case and your door is hanging or the lock isn’t working, then keep reading.

So if your uPVC door lock is broken or there’s another problem, here are some of the most common ones and what to do about them as a homeowner

#1. Loose door handle mechanism

A floppy door handle mechanism is a common problem. It can be easily fixed by you. You need to find the barrel and the screws that hold the lock in place. When you locate the screws or screw, tighten it with a screwdriver. This tightens the loose door handle and your door should now work properly.

#2. A faulty multipoint lock cylinder

Oftentimes, lower quality locks may have a faulty cylinder or they may break due to excessive usage. You can test this easily and rule it out. Insert your key and try to turn it. If it moves freely but the door won’t open or close, then the problem isn’t with the cylinder.

If the problem is with the cylinder, fixing it can be a cheaper option. You can buy and replace the cylinder only and not purchase the entire locking mechanism. You’ll also need to change the keys, so keep that in mind.

#3. Stuck uPVC door lock mechanism

If the uPVC door lock mechanism is sticking, the reason can be unlubricated or broken internal hinges. To find out what is making the mechanism stick, you’ll have to take it out to inspect it. However, if you’re not skilled at DIY handyman work, you should call a licensed professional to do it.  

If you decide to do the work yourself, inspect the hinges and if they need lubrication, you should lubricate them and see if the problem is fixed. 

#4. Broken gearbox

How to open a uPVC door with a broken gearbox? Do not try to force it open. This will result in breaking the door as well as the lock. There are a few things you can check that could be the reason for a broken gearbox, however, this isn’t a problem you can fix yourself. 

Regardless of the reason the gearbox is broken, you’ll need to use tools that only professional locksmiths have. If this is the problem your door has, then you should call a locksmith as soon as possible.  

Learn how the 24/7 locksmiths in London can help you out.

How to replace a uPVC door lock mechanism

In order to replace the broken door lock, first, you need to know how to remove a uPVC door lock mechanism.

Time needed: 1 hour.

  1. Prepare the tools.

    You’ll need a drill, a screwdriver, tape measure, a rubber mallet. 

  2. Remove the uPVC door lock mechanism.

    Use the screwdriver to unbolt the old lock and take it out of the door. Disassemble the handles and wiggle the mechanism out of the door.

  3. Identify your lock.

    Find the manufacturer’s name and mark on the faceplate if you want to buy from the same manufacturer. Buying the same brand will make it easier to fit the new lock because it will have the same dimensions, whereas locks from other manufacturers may be slightly different. 

  4. Measure before you replace the broken lock mechanism.

    Measure the main dimensions of the locking mechanism to get an exact-match lock or simply take the lock with you to the store.

  5. Replace the uPVC door lock mechanism.

    Insert the locking mechanism inside the door and then tighten the screws. If you’re having difficulty inserting the mechanism into the door, you can use the rubber mallet to gently hammer it in place. Then, adjust and tighten the handles.

  6. Test the lock.

    Do this with an open door. Insert the new key into the cylinder and turn it. Does the tongue come out properly? Does the key turn easily? 

Keep in mind that DIY lock replacements could lead to damaging the new mechanism, and make the job of the professional locksmith harder.

How Much Does it Cost to Replace a uPVC Door Lock Mechanism?

Changing a lock by yourself may be cheaper but it doesn’t have the many benefits as leaving it to a professional locksmith. In fact, if you’re not experienced enough and want to change your first lock, you may end up causing more damage and spending more money on fixing the problem than the initial lock replacement would have cost you.  

Book a professional locksmith with Fantastic Services and take advantage of emergency appointments with a 30-minute response, and a 6-month guarantee for the work done.

Wondering how much this will cost you? Take a look at our post on locksmith service prices!

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Having a broken door lock can be a burden and quite costly to fix. Hopefully, with this post, you’ll get oriented quickly and if possible, fix the problem quickly and by yourself. 

To sum it up, here are the key takeaways:

  • Any lock type can become damaged after some time and usage. It’s important to act fast. 
  • Paying a professional locksmith to fix the problem is often the safest, fastest, and in retrospect, the most cost-effective solution to such a problem.
  • DIY uPVC lock replacement is possible if you have the knowledge and the right tools. 


Did you find out what’s the reason for your broken uPVC door lock mechanism? Share your experience in the comment section below!

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