Locked out
uPVC door will not lock: is it broken, or just out of alignment?
Half of uPVC lock failures are not lock failures. Work through this before you pay anyone, because an alignment problem and a dead gearbox cost very different money.
The handle will not lift. Or it lifts, but the key will not turn. Or the door will not pull closed properly at all.
Before you ring anybody: a large share of these are not broken locks. They are doors that have moved, and doors that have moved can often be fixed for very little — sometimes for nothing.
Knowing which one you have is worth a couple of hundred pounds, because the two faults are priced completely differently.
How a uPVC door works, in one paragraph. Lifting the handle throws several locking points — hooks, rollers or bolts — up and down the edge of the door into the frame. Turning the key then deadlocks them. That whole assembly is the multipoint mechanism, driven by a gearbox in the middle, and separate from the euro cylinder that your key goes into. Three different parts, three different prices.
Work through this in order
1. Push or pull the door firmly, then try the handle
Do this first, every time.
uPVC doors expand in heat, contract in cold, and drop on their hinges over years. If the door has moved a few millimetres, the locking points no longer line up with the holes in the frame — so the handle jams, because it is trying to push metal into plastic.
Push the door firmly toward the frame — or pull it toward you if it is outward-opening — and lift the handle at the same time. If it suddenly works, you have an alignment problem, not a lock problem. That is a hinge adjustment, not a new mechanism.
2. Lift the handle fully before turning the key
This sounds obvious and it accounts for a genuinely large number of callouts.
The handle must go all the way up and stop before the key will turn. A partial lift feels like it has worked and has not. Lift firmly and deliberately, then turn.
3. Check the door has actually closed
Look along the edge. Is there a gap at the top or bottom? Is the seal compressed evenly? A door resting on its own weather seal has not shut, and it will not lock.
4. Look at the key and the cylinder
- Is the key bent, worn or a copy of a copy? Try the original if you have it.
- Does the key turn freely with the door open? If it does, the cylinder is fine and the problem is the door or the mechanism.
- Does it turn stiffly with the door open too? Then the cylinder itself may be failing.
That single test — does it work with the door open — separates the two main causes faster than anything else.
5. The handle spins loosely, or flops
If the handle moves with no resistance and nothing happens, the gearbox has likely failed. That is the component inside the mechanism that translates the handle movement into the locking points.
This is a real repair. It is also the one where you most want a written price first, because it is where quotes vary wildly.
Do not force a handle that will not lift. The gearbox is the weakest part of the assembly. Forcing a jammed handle is how an alignment problem, which costs a hinge adjustment, becomes a broken gearbox, which costs a mechanism. If it will not lift with firm pressure, stop.
What each fault should roughly cost
| Fault | What is actually needed |
|---|---|
| Door dropped or out of alignment | Hinge adjustment, sometimes a keep plate moved. A small job. |
| Euro cylinder worn or failing | New cylinder — insist on TS007 3-star or Sold Secure Diamond. |
| Gearbox failed | New gearbox, or the full mechanism if the part is obsolete. |
| Full multipoint mechanism | The largest of the four, roughly £150–£350+ fitted in normal hours. |
Indicative London figures are in what a London locksmith should cost, and you can sanity-check a quote you have been given with the price check tool.
The question to ask on the phone
When you do ring someone, this sentence saves the most money:
“The handle will not lift, but it does lift if I pull the door hard. Is that an alignment issue rather than a mechanism failure — and what is the total for each, including callout, labour, parts and VAT?”
You have just told them you know the difference. That changes the conversation considerably.
Be wary of anyone who quotes for a full mechanism replacement over the phone without asking a single diagnostic question. A competent locksmith asks whether the handle lifts, whether the key turns with the door open, and what the door is doing — because those answers determine the job.
If you are locked outside right now
Everything above assumes you are on the inside. If you are outside and the door will not open:
- Try the door hard while turning — a dropped door sticks shut as readily as it sticks open.
- Check every other way in before paying for a callout.
- Work through the seven things to do before you call anyone.
- If you rent, ring the landlord or agent first — a failed mechanism is their repair, not your bill. See who pays for a lockout.
Stop it happening again
A uPVC door that is beginning to drop gives you months of warning. The handle gets slightly stiffer. You start needing to pull the door a bit. You lift the handle twice.
That stiffness is the warning. Getting the hinges adjusted at that point is a small booked job in daylight. Ignoring it until the gearbox breaks — usually on a cold night, because cold shrinks everything — is a much larger bill at a much worse hour.
If your door is getting stiff, book someone now. That is the whole lesson.