uPVC Door Lock
When the key turns but the door won't lock, the cylinder is rarely the culprit — it's usually the multipoint mechanism hidden in the edge of the door. Knightsbridge Locksmiths repairs and replaces uPVC door locks, gearboxes and cylinders, and realigns dropped doors, for homes and businesses across Knightsbridge and London.
How uPVC Door Locks Fail
The way a uPVC door misbehaves points straight to the part at fault. A handle that lifts but won't lock, a key that spins, and a door you have to shoulder shut are three separate problems — describe yours and we'll arrive with the right gearbox or cylinder already on board.
Handle Lifts, Won't Lock
The lever raises but the key won't turn to throw the hooks — the classic sign the multipoint gearbox inside the door has failed.
Key Spins Freely
A cylinder that turns without engaging anything is usually worn or snapped, and needs replacing rather than forcing.
Door Has Dropped
If you're lifting or shoving the door to lock it, it has dropped on its hinges and pulled the mechanism out of line.
One Team for the Whole uPVC Door
Gearbox, cylinder, handles, hinges and keeps — the same engineer diagnoses and fixes the lot, with the price agreed before we travel and each part named on the invoice you get after.
Anti-Snap Where uPVC Is Weakest
The euro cylinder is the part of a uPVC door that thieves target, because a cheap one can be snapped in seconds. When we replace a cylinder we fit one rated to resist it, and check the whole mechanism while we're in there.
3-star anti-snap cylinders
TS007 3-star or Sold Secure Diamond cylinders that resist snapping, picking and bumping.
Correct gearbox, not a bodge
The exact multipoint mechanism for your door, sourced rather than substituted with a rough match.
Doors realigned on the hinges
Dropped doors lifted and adjusted so the hooks meet the keeps cleanly and lock without force.
Sized before we cut
Cylinders measured to the door so they sit flush, never left proud enough to grip and snap.
The Bit Most uPVC Repairs Get Wrong
We fix the cause, not the cylinder
A new barrel on a failing gearbox just fails again — so we diagnose the mechanism first, then fit what's actually needed.
Priced before we travel
Describe the door and the fault, and the quote you're given is the one you pay.
Parts on the van
The common gearboxes and 3-star cylinders are carried, so most jobs are finished in a single visit.
Local to SW1, SW3 and SW7
Run from Montpelier Street, minutes from Knightsbridge and the streets around it.
Getting Your uPVC Door Locking Again
- Describe the fault
Handle lifts but won't lock, key spins, or you're shoving the door — a photo of the lock edge helps.
- Diagnosed on site
We work out whether it's the gearbox, the cylinder, the alignment or all three before quoting a thing.
- Firm price, agreed
Repair or replacement costed and agreed with you before anything comes apart.
- Fixed and tested
Locked and unlocked through a full cycle, hooks seating cleanly, before we hand it back.
uPVC Door Work, Neighbourhood by Neighbourhood
uPVC doors turn up in different roles across Central London — here's what our uPVC door lock work tends to involve in four of the areas we're called to most.
uPVC Door Locks Knightsbridge (SW7)
Newer rear extensions on flats around Basil Street often have a uPVC door onto the garden, and the gearbox is the first thing to go with daily use. We carry the common mechanisms to fix it in one visit.
uPVC Door Locks Chelsea & Belgravia (SW3 / SW1X)
Shops and offices off King's Road with a uPVC back door need it locking reliably every night at close. We fit 3-star cylinders and service the mechanism so security isn't left to chance.
uPVC Door Locks South Kensington (SW7)
Conversions around Bute Street often still have the original builder-grade cylinder, which snaps easily. Swapping it for a 3-star barrel is a quick, low-cost security upgrade.
uPVC Door Locks Pimlico & Belgravia (SW1P / SW1E)
Houses around Warwick Way often have a uPVC side door that has dropped over the years and become a fight to lock. We realign it on the hinges so the hooks meet the keeps again.
Where We Repair uPVC Door Locks
Worked from 4 Montpelier Street in SW7, we reach Knightsbridge, Belgravia, South Kensington and Chelsea quickly for uPVC door faults, with wider cover across the SW1 postcodes and central London. A stuck handle or a snapped cylinder, the callout runs the same.
Knightsbridge & Belgravia
- Basil Street
- Walton Place
- Ovington Gardens
- Rutland Gate
- Chesham Place
South Kensington
- Bute Street
- Reece Mews
- Manson Place
- Astwood Mews
Chelsea & Brompton
- Sloane Avenue
- Sprimont Place
- Cadogan Gardens
- Elystan Street
Home or business, the order's the same: find which part has actually failed, fit the right gearbox or cylinder, and leave the door locking cleanly on the first try.
FAQs — uPVC Door Locks
Why does my uPVC door handle lift up but not lock?
That's the classic sign of a failed multipoint gearbox inside the door. The handle still moves, but it can't drive the hooks and bolts, so the key won't turn to lock. The gearbox needs replacing.
Can you replace just the cylinder, or the whole lock?
Either. If the mechanism is sound we can swap only the euro cylinder; if the gearbox has failed, that's replaced too. We diagnose which on site.
What is an anti-snap cylinder?
A cylinder built to break in a controlled way if attacked, so the working part stays protected. We fit TS007 3-star or Sold Secure Diamond barrels.
Why do I have to lift the handle hard to lock the door?
Usually the door has dropped on its hinges and the hooks no longer line up with the keeps. Realigning the door normally fixes it without new parts.
Do you carry uPVC parts with you?
The common gearboxes and 3-star cylinders, yes — so most uPVC door faults are put right in a single visit.
Is a snapped cylinder a security risk?
Yes — a snapped or worn cylinder can let a door be opened, so it should be replaced promptly with an anti-snap barrel.