Seven signs your deadlock is about to fail
Locks rarely die suddenly. They warn you for weeks first, and almost nobody listens until they are standing on the footpath at midnight.
Every lock we attend after a failure was telling its owner something for weeks beforehand. Here are the seven signals worth acting on, in roughly the order they appear.
1. The key needs to be jiggled
A key that only works at one particular angle means the pins or wafers are worn, the key itself is worn, or both. Once you are jiggling, you are one bad twist from a snapped key inside the cylinder.
2. The bolt needs a shoulder to throw
If you have to lean on the door to turn the key, the bolt is fouling the strike plate. That is usually a dropped door or a shifted frame rather than the lock, and it is a cheap adjustment now and an expensive lock replacement later.
3. The cylinder feels gritty
Grit in a cylinder means dust and old oil have combined into a paste. Never spray a lock with general-purpose oil — it accelerates exactly this. A dry graphite or PTFE lubricant is what belongs in a keyway.
4. The key comes out slowly or sticks
Sticky extraction usually means a burr on the key or a spring losing tension. Both are cheap fixes, and both end in a broken key if ignored.
5. The lock is loose in the door
Movement in the escutcheon or the handle means fixings are loosening in the timber. On heritage doors the screw holes eventually chew out entirely, which turns a tightening job into a repair-and-plug job.
6. Rust bloom around the face plate
Common on south-facing and exposed doors around Melbourne's inner north. Surface rust on the face plate usually means the internals are worse than the outside.
7. It is a 'double cylinder' deadlock on your only exit
Deadlocks that need a key to get out are a genuine fire risk if the key is not kept immediately at the door. If that describes your main exit, talk to a locksmith about a compliant alternative — this is a safety issue, not a convenience one.
The short version
- 01Jiggling keys and gritty cylinders are the earliest warnings.
- 02A hard-to-throw bolt is usually the door, not the lock.
- 03Use dry graphite or PTFE, never general-purpose spray oil.
- 04Key-both-sides deadlocks on a sole exit need review.
FAQ
Questions people ask us about this
- How long should a deadlock last?
- A quality deadlock in a well-hung door will run 15 to 25 years with occasional servicing. Coastal exposure, heavy daily use and cheap hardware all shorten that considerably.
- Can a worn lock be repaired instead of replaced?
- Often yes. Re-pinning, replacing springs, fitting a new cam or cutting a fresh key to code will revive a lock body that is otherwise sound.