EXPERT ADVICE
Help! My patio door won't lock - what do I do?
Updated 02/26
By: Lara Sargent
Reviewed: Alex Peters
It can be really frustrating if your patio door won't lock. But help is at hand with our troubleshooting guide which is packed with tips to help solve the issue.
Issues that may affect door locks
Things to try and fix the problem
Troubleshooting techniques
Quick fix ideas
Step-by-step lock fixes
When to call in a tradesperson
What it could cost to fix
Just like other parts of your home, over time, doors and locks can show signs of wear and tear and potentially go wrong.
You need patio doors to:
Open and close efficiently
Lock properly for safety reasons
Keep the elements out
See your garden space whatever the weather
Whether you have a stubborn uPVC door handle, a patio door that refuses to shut tight, or your sliding glass door won't lock, we're here to help.
Lock repair near me
If your door lock is stiff, temperamental or refuses to turn, you might be wondering if it can be repaired. Well, you’re in the right place! Here, we’ll cover everything to do with lock repair near you. Want to start finding a checked lock fixer near you? We have two quick and easy ways to find the
Where to start if your patio door won't lock
When it comes to reopening patio doors after being locked for winter, you might come across a few problems.
This could be a minor issue such as moving parts seizing up due to rainwater getting in. In that case, oiling the lock might do the trick.
uPVC doors not locking can happen in either cold or hot weather.
As a starting point, first check:
Is the lock obstructed?
Has the door come off its track?
Has anything expanded due to heat?
Has any water got into the lock mechanism?
There are things to check. Not just in the lock, but look all around the door to see if anything is trapped or blocking movement.
Making sure the door slides freely will mean it can lock properly. You might need to get in touch with a patio door repair specialist to help with this.
Ensure the whole patio door installation is plumb (level). Once fixed in place, it is incredibly hard to take it out and start all over again, having a misalignment can really impact the door's function.
Reasons why your patio door won't lock
Various factors can affect the locking mechanisms.
As well as standard wear and tear, obstructions and particularly hot weather, here are some other things to consider:
Is the door misaligned?
Everything needs to fit together to work smoothly.
Handles that won't lift up to lock when your uPVC door is closed (but lifts easily when the door is open) might mean the door needs adjusting. Sometimes the lock latch might need adjusting too.
Is there debris in the lock?
Dirt, dust, and debris can build up in the lock mechanism and make it stick or not shut properly.
Check the frame and locking points for any debris or small stones/gravel that might be causing an obstruction.
Are there faulty or worn parts?
Over time, the moving parts of a patio door will wear and can lead to problems with a door locking.
A gearbox failure is one of the most common parts that might need fixing or replacing. Located inside the door, the gearbox is a smaller part of the multipoint mechanism that turns a number of rollers, hooks, and bolts. It ensures the door is securely locked.
Other potential reasons your patio door won't lock:
Key stuck in the lock
Alignment of the strike plate
Broken key
Dropped door
Full uPVC lock mechanism replacement
Jammed lock
The weather has caused expansion/contraction
If you've tried everything, it could be time to update your patio door, for something that isn't as problematic.
How much does it cost to replace a patio door?
Need to replace your patio doors? Whether you're fixing a broken door or updating your patio design, this is a task best left to the professionals.
Solutions for fixing patio doors
Whether your patio has french or sliding doors, here are some common solutions for fixing the problem:
1. Clean and lubricate the lock
Remove any visible dirt and debris using a soft brush or damp cloth. For hard-to-reach areas, consider using a can of compressed air to blow away any stubborn grime.
After cleaning, lubricate all moving parts with a light machine oil.
2. Check for worn components
If possible, assess the condition of the components in your door lock, especially if you have an older door.
Check for signs of wear on the handle, cylinder, and lock hardware. And if any parts appear damaged or worn, it may be time to replace them.
3. Realign the doors
Even if your doors have only shifted slightly, the locking points might not meet as they should.
This can be a complex process and can include taking all the mechanisms apart including removing panels and hinges from the door.
For this reason, it is a good idea to get in touch with a local patio door repair expert who can make the adjustments.
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How to fix a patio door lock
You might be able to save yourself some money by trying to fix a patio door lock yourself.
If you're more confident with DIY and your patio door lock is sticking, fear not.
Here's how to bring it back to life with a little TLC:
Gather your tools: Screwdriver, lubricant (and a little bit of patience!)
Disassemble the lock: Carefully remove the lockset following the manufacturer’s guidelines
Clean and lubricate: Spruce up the components and apply a recommended lubricant
Reassemble the lock: Put the lockset back together as you found it, making sure each piece is snug and secure
Unsuccessfully repairing a door lock yourself could invalidate your home insurance, leaving you in a really difficult situation and a heavier repair cost.
Patio locks and latches: Master your door security
Fasten your seatbelts (or, in this case, your patio doors), as we journey through the labyrinth of locks and unveil the secrets behind impeccable security.
How to fit a patio door lock
Installing a new lock? Let’s fit it perfectly to make sure your patio’s security is top-notch.
Choose the right lock: Depending on your door type, select a suitable lock. For example, lever locks for swinging doors, mortise locks for sliding ones etc.
Read the instructions: Don’t skip this step – each lock has a unique installation process you need to follow
Measure and mark: Use a tape measure and pencil to mark the right position for your lock on the door
Drill and install: Carefully follow the instructions for drilling holes and attaching the lockset
Test and adjust: Test the lock’s functionality and make any necessary adjustments for a perfect fit
Need some more information to feel confident before beginning?
How to change a uPVC door lock
Are you having problems with your uPVC door lock? Have several parts been replaced or repaired but it’s still not working like it should? If this sounds like you, read on to find out all you need to know about how to change a uPVC door lock.
How to replace a sliding patio door lock
If your sliding door lock is showing signs of wear or simply isn’t up to the task anymore, it’s time to replace it.
Remove the old lock: Unscrew and remove your current lock (follow the manufacturer’s guidelines!)
Measure twice, buy once: Measure the dimensions of your old lock to make sure your replacement will seamlessly fit
Install the new lock: Attach the new lock, making sure it’s level and secure
Test and verify: Test the lock to make sure it engages and disengages smoothly before patting yourself on the back
If in doubt, lock in the help of a reliable locksmith or relevant tradesperson in your local area!
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How much does it cost to replace a uPVC door lock?
The average cost of a uPVC patio door lock replacement is £110, plus the cost of labour.
The typical locksmith hourly rates are on average £75. If you wish to get your uPVC door lock changed, that takes around 1 - 3 hours generally, depending on various factors.
Why not try out our job estimator to find out what you could expect to pay in your local area?
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Of course, if you want your door locks changed out-of-hours, that would cost you more per hour. Most locksmiths’ hourly rates for such a situation would be between £75 - £125.
Wondering how to find trusted, experienced tradespeople to get your patio doors working smoothly again? Checkatrade can help.
Finding a trade with Checkatrade
When hiring any locksmith or patio door specialist, we know how important it is to find someone you can trust to be committed to quality.
That’s why at Checkatrade we only take on trades who pass up to 12 checks and commit to upholding The Checkatrade Standard to:
Deliver a high quality of workmanship
Maintain high standards of personal conduct
Work safely, ethically, and within their skill set
Communicate clearly and honestly
Agree costs and contract terms upfront
Encourage and welcome customer reviews
We also check all the reviews our tradespeople receive are from real people so you can be sure they’re the real deal.
Find and book a trade through us, or pay via the app, and we'll guarantee their work for up to £1,000. Eligibility and T&Cs apply.
See the tradespeople we've checked for your job