If the handle lifts and the key turns with the door open but not with it shut, the mechanism is usually fine and the door is out of line with the frame. The hooks, rollers or bolts are catching on the keeps instead of sliding in. A small adjustment to the keeps, rollers or hinges usually fixes it.
The open door test is the quickest way to tell. With the door open, lift the handle gently and turn the key. If both move smoothly, the gearbox inside the door is doing its job. When the same handle sticks once the door is shut, the locking points along the edge of the door are meeting the keeps in the frame in the wrong place, so they bind.
The Master Locksmiths Association's guide says a uPVC door that will not lock when it is closed is down to alignment, and that in most cases it is easy to fix by adjusting the keeps, the roller points or the hinges. The same guide says being 1mm or 2mm out of alignment is enough to stop a door locking or unlocking.
Common signs that the door has dropped on its hinges are the door catching on the frame, uneven gaps around the edge, and having to lift or pull the door to make it close. Fresh scrape marks on the keeps, or on the hooks and rollers, show where they are catching. You can check all of this without taking anything apart.
Do not force the handle to make it lock. The MLA guide warns that poor alignment adds wear to the gearbox and multipoint lock and can make them fail, and another locksmith guide notes that a gearbox under load can fail completely. Forcing it every night can turn a short adjustment into a new mechanism.
Realigning a uPVC or composite door that will not lock costs £110 on weekdays from 8am to 6pm, £140 on evenings and weekends, and £150 at night from 10pm to 8am. That price includes travel and up to one hour on site, and it is fixed before we set off.
Related questions
- Why won't my uPVC door handle lift up?
- How to fix a uPVC door that won't lock?
- Why won't my uPVC door lock in hot or cold weather?
