When you lift the handle on a uPVC or composite door and turn the key, the door locks at several points along its edge at once. That is the multipoint lock. When it starts to go wrong, it usually gives plenty of warning before it fails completely. Spotting the signs early often means a simpler repair — and avoids being locked out, or locked in, at an awkward moment.
How a multipoint lock works
Along the locking edge of the door is a long metal strip. Behind the handle and cylinder sits a central gearbox, connected by rods to hooks, rollers or bolts positioned above and below it. Lifting the handle drives those hooks and rollers into keeps fitted in the door frame; turning the key then locks them in place.
Because every locking point has to line up with its keep in the frame, the lock depends on the door sitting correctly. That is why so many multipoint problems start with the door itself rather than the lock.
The warning signs
Look out for any of the following:
- The handle is stiff to lift, or you have to push or pull the door before it will lock.
- The key is hard to turn, or will only turn part of the way.
- The handle feels loose or floppy, or drops without springing back to level.
- The handle lifts, but the hooks or bolts do not seem to engage.
- The door catches on the frame, or the gap around it looks uneven.
- You can hear grinding or clicking from inside the door when you operate it.
- The door locks but will not unlock, or will not lock at all.
The first few are early signs. The last one needs dealing with straight away.
What usually causes it
The door has dropped or moved. Over time, doors can drop on their hinges or shift in their frames. The locking points then no longer meet the keeps squarely, and extra force is needed to lift the handle.
Temperature changes. uPVC expands and contracts with the weather, so a door that is fine in winter can become stiff in summer, or the other way round.
A worn gearbox. The gearbox takes the strain every time the handle is lifted. When a door is out of line, forcing the handle puts extra load on it until parts inside wear or break. A floppy handle is often a sign of a broken gearbox.
A worn cylinder. If the key is stiff but the handle lifts easily, the cylinder may be the problem rather than the multipoint mechanism. A worn cylinder or a damaged cam can also stop the key turning at all.
Worn or loose keeps. The keeps in the frame can work loose or wear, so the hooks do not engage properly.
What not to do
- Do not force it. If the handle or key is stiff, something is usually out of line. Forcing it is the most common way a gearbox gets broken.
- Do not ignore it. A stiff door tends to get worse, not better. One that will not lock is a security problem, and one that will not open can leave you locked out.
- Do not rely on lubricant alone. A light lubricant on the moving parts along the edge of the door can help if things are simply dry, but it will not fix a door that has dropped or a gearbox that has failed.
Repair or replace?
A failing multipoint lock does not always mean a new lock. Depending on the cause, the fix might be:
- Adjusting the door. Hinge and keep adjustment can bring the door back into line, taking the strain off the mechanism.
- Replacing the gearbox. If the gearbox has failed, it is often possible to replace just that part rather than the whole locking strip, provided a matching gearbox is available.
- Replacing the whole mechanism. Older or discontinued mechanisms sometimes cannot be matched, in which case a full replacement or a compatible retrofit is needed.
- Replacing the cylinder. If the cylinder is the problem, it can be changed on its own. This is also a good moment to fit a certified anti-snap cylinder — see our guide to TS007 3 star and Sold Secure Diamond cylinders.
Identifying which part has failed is the key to not paying for more than you need.
When it becomes urgent
If your door will not lock at night, or will not open at all, treat it as urgent. A door that cannot be secured leaves the property vulnerable, and a jammed mechanism can mean you are locked out or locked in. In those situations our emergency locksmith service can help. If you are locked out and are worried about who to call, our guide to what to do when you are locked out covers the questions to ask.
Looking after your door
A few simple habits help a multipoint lock last:
- Close the door fully before lifting the handle, rather than using the handle to pull it shut.
- Keep the locking points and keeps clean, and lubricate them lightly from time to time.
- Pay attention when the door starts to feel different. An early adjustment is quicker and cheaper than a broken gearbox.
How we can help
We diagnose and repair multipoint locks on uPVC and composite doors, replacing only the part that has failed wherever that is possible. Read more about our multipoint lock repairs and uPVC door lock repairs, or check the areas we cover across Essex and East London. If your door is showing any of these signs, call 07500 582013.