uPVC Door Lock Repair & Window Lock Repair in London
uPVC Door Won’t Lock? The Faults We Fix Most
Handle Will Not Lift or Lock
A lever that is stiff, floppy or stuck down usually means a worn gearbox or a broken spring. We test the mechanism and replace the failed part.
Gearbox FixesKey Will Not Turn or Has Snapped
A stiff or broken Euro cylinder can leave the door half locked. We remove broken keys, test the cam and replace the cylinder if needed.
Cylinder ReplacementDropped or Dragging Door
Worn hinges or a sagging door make the bolts miss their keeps. We adjust the hinges and keeps so the door closes and locks without slamming.
Hinge & Keep AdjustmentWindow Handles and Locks
Loose, broken or seized window handles leave rooms unsecured. We repair or replace them on casement and tilt-and-turn windows.
Window HardwarePatio and French Doors
Sliding and French doors have their own hooks and bolts. We repair or replace the mechanism so the doors lock firmly and glide again.
Patio Lock RepairCylinders That Can Be Snapped
Many uPVC doors still have cylinders a burglar can snap in seconds. We fit correctly sized TS007 3-star cylinders that resist snapping, bumping, drilling and picking.
TS007 3-Star UpgradeuPVC Door Mechanism Repair Without a New Door
uPVC Window Lock Repair and Door Security Checks
Cylinder Upgrades
Ordinary cylinders replaced with TS007 3-star versions where it makes sense, cutting the risk of lock snapping.
Hinges and Keeps Adjusted
Small adjustments take the strain off the lock, make the door smoother and help the mechanism last for years.
12-Month Workmanship Guarantee
Parts and fitting are covered for 12 months, with a written record of the work.
Find the Failed Part, Fix It, Test Every Point
Tell Us What It Is Doing
The door type, what the handle and key do, and whether it is locked or stuck open right now. A photo of the door edge helps.
Advice on keeping it secureWe Test and Quote
We test each part, find the one that failed and give you a written price before we touch it.
Repair option explainedWe Repair and Test
The part is repaired or replaced, the door lined up and every locking point tested with you.
Every point testedHow Much Does a uPVC Gearbox Replacement Cost?
For dropped doors, loose handles and keeps that no longer line up.
- Hinge and keep adjustment
- Handle tightened or replaced
- Moving parts lubricated
- Every locking point tested
For doors that will not lock, lift or turn because a part has failed.
- Fault found on site
- Gearbox or cylinder replaced
- TS007 3-star option
- New keys supplied and tested
For doors with several faults, repeat failures or security worries.
- Whole lock system checked
- Window hardware checked
- Upgrade advice
- 12-month workmanship guarantee
Written Price Before Work
Our price covers your area with no congestion charge, parking or travel extras.
uPVC Lock Repair FAQs
Why won’t my uPVC door lock?
The most common reason is a door that has dropped, so the hooks and bolts no longer line up with the keeps in the frame. A worn gearbox or a failing cylinder can also stop it locking. We check each part in turn, adjust or replace what has failed, and test every locking point.
My uPVC door handle won’t lift. What is wrong?
If the handle will not lift to throw the bolts, the door is often binding against the frame, or the gearbox inside the door has worn out. Do not force it, as that can snap the mechanism. We test the door alignment and the gearbox to find which one is at fault.
How much does a uPVC gearbox replacement cost?
A 2026 price guide puts a uPVC multipoint mechanism replacement at about £120 to £250 in normal hours (BestBuilders). The price depends on the make and length of the mechanism. We identify the exact part first and give you a written quote before fitting it.
Do I need a new door if the lock has failed?
Almost never. Locks, gearboxes, cylinders and handles are all replaceable parts. A new door is only worth considering if the frame is badly damaged, the glazing has failed or the door cannot be adjusted. We will tell you honestly if that is the case.
My key is stuck or the door is half-locked. What should I do?
Do not force the key or kick the door, as that causes more damage. Try lifting the handle fully while gently turning the key. If it will not release, call us. We can usually free the lock, take out a broken key and make the door secure again.
Can you repair uPVC window locks too?
Yes. We repair and replace window handles, espagnolette mechanisms and locks on most casement and tilt-and-turn uPVC windows. Send us a photo of the handle and the edge of the opening window, and we will confirm the part before we come out.
Are my uPVC door cylinders at risk of snapping?
Older Euro cylinders without anti-snap protection can be broken quickly by burglars. A TS007 3-star cylinder resists snapping, bumping, drilling and picking. We check whether yours sticks out past the handle or is below standard, and fit a correctly sized replacement.
Cylinder, Gearbox or Adjustment?
Not sure what your uPVC door needs? Call us for practical advice.
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