Guide
Urgent Lock Problem? Repair or Replacement: Working Out Which Your Door Needs
Your key has turned stiff, the handle has started to sag, or the door no longer locks the way it used to, and you want to know whether you are paying for a repair or a whole new lock. Here is the short answer: a door lock is not one object. It is a small set of parts working together, so the question worth asking is which part has given up, and whether that part can be changed by itself.
That is what this guide settles. A good share of the jobs people call lock repairs turn out to be one component swapped while everything else stays put. There are also a few situations where a new lock is the sounder choice even though a repair would technically work. It covers narrowing down the fault, which parts come out separately, what moves the cost, and what to ask before agreeing to work. If you would rather someone looked at the door, Runcorn Locksmith takes emergency calls around the clock, every day of the year, on 01928 611001.
Call with your postcode for a current arrival estimate.
- 24-hour emergency cover
- No call-out charge
- Price agreed before work starts
Which Part Has Actually Failed?
On a typical UK door the lock is really four or five separate parts, and a symptom usually points towards one of them rather than the whole assembly. So a stiff key, loose handle or door that will not lock does not automatically mean a whole new lock. Use the table as a map of where to look, not as a verdict on your own lock: one symptom can have several causes, so avoid forcing the mechanism or buying parts until the fault has been pinned down.
| Symptom | Likely part | Usually replaceable on its own? | Relative cost |
|---|---|---|---|
| Key turns freely but the bolt does not move | Likely the cylinder or its cam; sometimes the lock case or multipoint behind it | Usually, if the damage stops at the cylinder | Low, unless the mechanism behind it has also failed |
| Key will not go in, or will not turn, with the door open | Likely the cylinder, or a worn key | Usually | Low |
| Handle lifts but nothing engages | Likely the multipoint gearbox | Often, depending on whether a matching part can be found | Middle to high |
| Bolt or latch only catches when the door is shut | Likely the keep or the hinges rather than the lock | Yes; the keep is often adjusted rather than replaced | Lowest |
| Handle droops or feels loose | Likely the handle or the spindle | Usually | Low |
| Stiff through the whole turn with the door open | Likely wear inside the cylinder or the lock case | The cylinder usually; the case sometimes | Low to middle |
Before reading across a row, try the lock with the door open, as set out in how to replace a door lock, because that one check separates a lock fault from a door that has moved. As a rule of thumb, repair tends to make sense when the trouble comes down to alignment or one replaceable part and the rest of the mechanism is still dependable. A replacement tends to make more sense when several parts are worn, compatible components cannot be sourced, the lock has taken serious damage, or it no longer gives the door adequate security. For a fuller picture of what each type of door lock is made of, see the lock types guide, and for the work itself, see the lock repairs we carry out.
The Parts That Can Be Changed on Their Own
On most UK doors the lock is built in modules, so a part that has failed can usually be taken out without disturbing the rest. That gives you the single most useful question to put to anyone quoting: what, exactly, is being replaced? Fitting a new cylinder is not fitting a new lock, and the two should never be priced as though they were. Not every part is swappable, though. Some locks are made in one piece, and some components for older locks are no longer produced.
Cylinders, Handles, Latches and Keeps
These four sit at the inexpensive end of the door, and each one can come off without the others being touched.
- Cylinder. The barrel the key turns, either a euro cylinder or the rim cylinder on a nightlatch. It is replaced more often than any other part of a door lock, and a failing one tends to feel gritty, stiff or sloppy.
- Handle and spindle. Between them they drive the latch and, on a multipoint door, the mechanism inside the edge. A drooping handle is usually the handle itself or a worn spindle, not the lock.
- Latch. The sprung tongue that holds the door closed when it is not locked. A tired latch sticks or fails to spring back out.
- Keep. The plate on the frame, also called the strike plate, that the bolt enters. It gets adjusted far more often than it gets replaced.
A competent DIYer can deal with three of these four, and moving the keep is frequently the cheapest fix anywhere on the door. The practical side, including how a replacement lock is measured and fitted, has its own guide.
The Multipoint Gearbox, Which Is Its Own Question
On a uPVC or composite door, the gearbox fails more often than anything else, and it is also the part most often mistaken for the cylinder. Keep three facts apart:
- The cylinder is the part the key turns.
- The gearbox is the unit inside the door edge that the handle drives.
- The gearbox is what throws the hooks and bolts into the frame.
So when the key turns but the handle will not lift, or the handle lifts and nothing locks, the cylinder is probably fine and the gearbox probably is not. A gearbox job counts as a repair in the sense that you keep the door, but the gearbox itself is swapped for a new one, and whether a match can be found depends on the age and maker of the door. Where none can be found, the whole multipoint strip goes in instead. On cost, a gearbox sits well above a cylinder swap and well below a new door. Faults on these doors are covered in more depth under uPVC door lock repair and replacement and in the guide to uPVC lock mechanism problems.
Rekeying or a New Cylinder: What Are You Being Offered?
Rekeying leaves the lock where it is and changes which key operates it, whereas a cylinder change takes out the part the key goes into and fits a fresh one. Both stop the old keys working, but they are different jobs at different prices, so it is worth knowing which one a quote describes. If new cylinders are on the table, it also helps to know what makes one cylinder more secure than another.
What Rekeying Actually Changes
Mechanically, rekeying alters the pins inside a pin tumbler cylinder so that they suit a different key, and every key cut for the old pins stops working. It earns its place in two situations:
- A property with several locks that you want working from one key, known as keyed alike.
- Hardware you would like to keep, because you like it or because it matches the rest of the building.
What it cannot do is help a lock that is worn, damaged or the wrong specification, since the same mechanism goes straight back into the door. So ask yourself why the job is needed. If a key has gone missing, rekeying answers that. If the lock itself no longer works properly, it does not. Master key suites are a separate subject outside this guide.
When Swapping the Cylinder Is the Simpler Answer
A standard euro cylinder is held by one fixing screw through the edge of the door, which is why a straight swap is often the quicker route; changing a cylinder on a uPVC or composite door explains how that works. A new cylinder arrives with its own set of keys, so it closes the lost-key problem just as rekeying does. It also lets you change the specification in the same visit, so a worn basic cylinder can become a better one for the difference in part cost, which rekeying cannot offer. Across several doors at once, though, the sums can tip the other way. Before agreeing, ask:
- Is this quote for rekeying, or for new cylinders?
- What specification is the new cylinder, and what is the old one?
- What would the other option cost for the same doors?
| Rekeying | New cylinder | |
|---|---|---|
| What changes | The pins inside the existing cylinder | The whole cylinder |
| Old keys | Stop working | Stop working |
| Specification | Stays the same | Can be raised at the same time |
| Worn or damaged lock | Not fixed | The cylinder is renewed; parts behind it are not |
Fixing one part is worthwhile when a single identifiable component has failed and the other parts can still be relied on. It becomes less practical when the part needed is obsolete, does not fit, or is hard to get hold of, which happens more with older, unusual or discontinued locking systems. A wider replacement is also worth weighing when several components have worn at once, when nobody can be sure who holds a key, or when the existing lock no longer suits the door.
When Repair Is Possible but Still the Wrong Answer
A lock can be in perfect working order and still be the wrong lock to keep. A repair answers a mechanical question: does it open, close and lock as it should? Some of the situations below are not mechanical at all, and fixing the mechanism leaves them exactly where they started. If a door has been forced, see our page on securing a door after a forced entry.
After a Lost Key or a Forced Entry
When the real issue is who can open the door rather than whether it opens, repairing the mechanism changes nothing. Two cases come up again and again.
- A lost or stolen key. The lock may carry on working normally, but there is now a working key somewhere you cannot see, and it will open the door for whoever holds it. No repair stops an existing key from turning, so getting back control of access becomes the priority. Think about whether the key could be traced to your address, whether anything with your details went missing alongside it, who has held a copy in the past, and whether other copies might be unaccounted for. If those answers are uncertain, the cylinder needs changing even though nothing is broken. If you are also stuck outside, see getting back in when the key is gone.
- A forced entry. The lock may still turn, but it has been loaded in ways it was never designed for, and damage inside a cylinder or lock case is not always visible from outside. If an insurance claim is involved, photograph the damage before anything is changed, and ask the locksmith to list every part they replace. The wider steps are set out in what to do after a break-in.
When a Standard or a Policy Condition Applies
Where a policy names a lock standard, a repair that leaves the original specification in place may not meet it. Some policies specify BS 3621 for certain external doors, and requirements vary by insurer, door type and policy. A repair preserves whatever lock is on the door today, so if that lock never met the standard your policy names, fixing it does not change that. A replacement is the point at which the specification can be brought up. The standards themselves are explained in the BS 3621 guide. Before you decide:
- Read the security condition in your own policy wording.
- Ask the locksmith, in writing, which standard the part they plan to fit meets.
Locksmith pricing
What the Two Options Realistically Cost
The shape matters more than any single figure. A component swap sits at the bottom, a whole lock in the middle, and a mechanism job above both. What decides where a job lands is mainly the part that failed, the type of lock, the parts needed, and whether the door or frame also needs attention.
Two rules count for more than the numbers. First, ask what exactly is being replaced: a useful quote spells out what will be adjusted, repaired or renewed instead of calling every job a lock change, and a cylinder quoted as a lock change is the commonest way a fair price turns into an unfair one. Second, ask what is not included, because parts, VAT and the time of day all move the total.
There is no call-out charge at any hour, and every job is priced on the call from what you describe, with any change found on site explained before work begins. You pay for the work carried out, any parts needed, and VAT. Rates outside Monday to Friday, 7am to 6pm, are higher, but the call-out itself is never charged.
For the figures and where they come from, see what locksmith work costs, with the figures, or call 01928 611001 for a price on your own door.
Keep or hinge adjustment.
The lowest step; what moves it is how far the door has dropped or shifted.
Cylinder, handle or latch.
Low; moved by the specification chosen and the number of doors.
Whole lock, such as a mortice case or nightlatch.
Middle; moved by lock type and security specification, since cases and latches vary widely in design and quality.
Multipoint gearbox or full strip.
The top step; moved by whether a matching part exists. Older or less common components take longer to identify, and when no compatible part turns up, a wider replacement follows.
Doing It Yourself or Getting It Done
Which jobs you take on should follow the component, not your confidence. Before attempting anything, remember that forcing a stiff key or handle can turn a small fault into a bigger one.
Reasonable to attempt
adjusting a keep, changing a handle, or swapping a rim or euro cylinder where the measurement is straightforward.
Possible, but easy to get wrong
a mortice case, where the recess in the door and the keep on the frame both have to line up.
Better left to a locksmith
a multipoint gearbox, anything on a fire door or a flat entrance door, and any lock with a key snapped inside it, because a fragment left in the keyway turns a small job into a larger one. See what to do when a key is stuck in the lock, or our page on.
This parts list is the one a locksmith works from, so knowing which part failed gets you most of the way to a fair quote.
Have the Lock Looked At in Runcorn
We will look at the door, tell you which part has failed, and quote for both the repair and the replacement, so the decision stays yours. When you ring, have three things ready: what the door is made of, the symptom in plain words, and whether it happens with the door open or only when it is shut. A clear photograph of the lock and the door edge helps too.
- No call-out charge, at any hour
- Emergency calls taken 24 hours a day, every day of the year
- [PROVIDER PACK: DBS check evidence for technicians]
- [PROVIDER PACK: insurance held and evidence]
- A price on the call from what you describe, with anything found on site explained before work begins
Get the Lock Diagnosed: call or message Runcorn Locksmith on 01928 611001.
Repair or Replace Questions
Is it worth repairing a lock rather than replacing it?
Often, yes. When the fault comes down to door alignment or one part that can be swapped, a repair is usually worth considering. Replacement tends to suit a lock with several worn parts, heavy damage, components that cannot be sourced, or doubt over who holds a key.
Can an old lock still be repaired?
It can be, provided the fault is limited, compatible parts can still be found and the rest of the mechanism is dependable. When several parts have worn, components are obsolete, or the lock no longer suits the door, replacing it is usually the more practical route.
Will oil or spray fix a stiff lock?
Only if the lock simply needs routine maintenance and the right product is used. Lubricant will not correct a door that has dropped, worn components or internal damage. Go by the lock maker's guidance rather than reaching for oil or a general-purpose spray.
Does a repaired lock work as well as a new one?
A repair done properly can bring back reliable operation, as long as the correct fault was found and suitable parts were fitted. What it cannot do is change who holds keys or raise the lock's specification.
What should I send before asking for a quote?
The door material, a description of what the key and handle are doing, and clear photographs of the lock and the door edge. Photos can often help identify the locking system before anyone arrives.
What if the locksmith finds a different fault on site?
The proposed work and the price should be explained before anything starts. If the inspection turns up a different fault, ask for the revised work and the new total to be confirmed before they carry on.