Locks don’t announce their retirement. They don’t send a memo warning you they’re about to fail. Instead, they whisper—and most people aren’t listening.
Why Lock Health Matters
A failing lock creates two problems. The obvious one: it might leave you locked out at the worst possible moment. The hidden one: a worn lock is a weak lock, and criminals can sense weakness.
Burglars often test doors before committing. A lock that feels loose, looks old, or operates poorly tells them this is an easier target than the neighbour’s door with the crisp, solid mechanism.
"The cost of lock replacement is measured in pounds. The cost of ignoring warning signs is measured in everything you own.
Sign 1: The Key Sticks or Requires Jiggling
What’s Happening
When you need to wiggle, jiggle, or apply unusual pressure to turn your key, the internal pins are no longer aligning properly. This happens because of:
- Wear on the pins and springs - Years of use grinds down precision components
- Debris accumulation - Dust, grit, and oxidation inside the mechanism
- Key wear - Your original key may have worn down
- Misalignment - The door or frame has shifted
When to Worry
Occasional stiffness in cold weather is normal. Daily struggle is not.
The Solution
Try a fresh key first—worn keys are often the culprit. If a new key doesn’t help, the mechanism needs attention. Professional assessment can determine whether cleaning/lubrication will suffice or replacement is needed.
Sign 2: The Cylinder Wobbles or Feels Loose
What’s Happening
If the cylinder moves when you touch it—rotating slightly or shifting in and out—the fixing screw inside has failed or the cylinder has been damaged.
Why This Is Serious
A loose cylinder is a gift to criminals. It’s already half-attacked. Minimal additional force can snap it completely, giving instant access.
The Solution
This isn’t a “schedule it for next week” issue. Replace the cylinder promptly. While waiting, a temporary security measure like an internal door chain provides minimal backup protection.
Sign 3: Visible Damage or Rust
What to Look For
- Corrosion around the keyhole or cylinder face
- Scratches near the keyway (potential picking attempts)
- Cracks in the cylinder housing
- Discolouration from oxidation
What It Means
Surface damage indicates either weather exposure degrading the mechanism or previous attack attempts. Either way, the lock’s integrity is compromised.
Sign 4: The Lock Turns Too Easily
The Problem Most People Miss
A lock should offer comfortable but noticeable resistance. If your key spins like it’s moving through butter, the pins are no longer providing proper engagement.
Why This Happens
- Severely worn pins that no longer reach proper height
- Damaged key that’s worn to match the worn pins
- Internal spring failure
The Risk
A lock with no resistance can often be bypassed with improvised tools. The security has fundamentally degraded.
Sign 5: Your Lock Is Over 10 Years Old
The Technology Gap
Lock security has advanced dramatically. A lock fitted in 2015 likely lacks:
- Anti-snap protection
- Anti-bump features
- Modern anti-pick pins
- Restricted key systems
When Age Alone Justifies Replacement
Even if your old lock functions perfectly, it may offer security standards that were acceptable a decade ago but inadequate today. Technology moves on; so do criminal techniques.
Sign 6: You’ve Lost Keys (or Can’t Account for Copies)
The Hidden Vulnerability
Lost keys aren’t just inconvenient—they’re security liabilities. You don’t know where they are or who might have them.
Consider:
- Did you ever lend keys to contractors, cleaners, or previous tenants?
- Could lost keys be identified as belonging to your property?
- Have keys been stolen (even if nothing else was taken)?
The Only True Solution
Rekeying or replacing the cylinder is the only way to eliminate this risk. All those copies, wherever they are, become useless.
Sign 7: Your Insurance Doesn’t Recognise Your Lock
The Policy Problem
Many insurance policies now specify minimum lock standards:
- BS3621 for mortice locks on wooden doors
- TS007 3-star for cylinders on uPVC/composite doors
- Sold Secure certified products
The Claim Nightmare
If your locks don’t meet policy requirements, insurers may:
- Reduce claim payouts
- Void claims entirely for “failure to maintain reasonable security”
- Increase future premiums
Checking Your Coverage
Review your policy documents or contact your provider. Ask specifically what lock certifications are required for full coverage. See our complete guide on locks and insurance requirements.
Repair vs Replace: The Decision Framework
When Repair Makes Sense
- Stiffness from debris that can be professionally cleaned
- Minor issues with the door alignment rather than the lock itself
- Premium locks under 5 years old with manufacturer warranties
When Replacement Is the Answer
- Any sign of visible damage
- Loose or wobbling cylinder
- Lock over 10 years old
- Unknown key copies in circulation
- Failure to meet insurance or modern security standards
- Repeated problems despite repairs
"A quality replacement lock costs between £80-150. The average burglary costs over £3,000 in losses alone—before considering emotional impact and increased insurance premiums.
How to Inspect Your Locks Yourself
Walk around your property and check each external door:
- Visual inspection: Look for rust, cracks, scratches
- Wobble test: Push and pull the cylinder gently—any movement is bad
- Operation test: Key should turn smoothly without force
- Protrusion check: Cylinder shouldn’t extend more than 3mm from the door furniture
- Age assessment: Do you know when the lock was installed?
- Documentation check: Any visible certifications or brand markings?
Frequently Asked Questions
How do I know if my lock is failing?
Warning signs include stiffness when turning, needing to jiggle the key, the handle feeling loose, grinding sounds, or the lock not engaging on the first attempt.
Should I repair or replace a faulty lock?
Simple issues like stiffness often respond to lubrication. However, worn internal components, loose mechanisms, or visible damage usually require replacement.
How long do quality locks last?
High-quality locks last 10-15 years with proper maintenance. Budget locks may fail in 3-5 years. Regular use, weather exposure, and maintenance affect lifespan significantly.
Does a stiff lock mean it's failing?
Not necessarily. Stiffness often results from lack of lubrication or minor alignment issues. Try graphite lubricant first. If stiffness persists, the mechanism may need professional attention.
How often should locks be replaced?
There's no fixed schedule, but assess locks every 5 years and seriously consider replacement at 10 years regardless of condition. Technology advances make older locks increasingly vulnerable.
Can a locksmith repair rather than replace?
Sometimes. Issues like debris, minor misalignment, or worn keys can often be addressed without replacement. Physical damage or wear to internal components typically require replacement.
Should I replace all locks at once?
If one lock is showing signs of failure and others are similar age and type, there's practical benefit to upgrading together. You can also have them keyed alike for convenience.
Is it worth upgrading locks if I have a burglar alarm?
Multiple security layers work together. A lock deters and delays entry; an alarm alerts to a breach. Neither replaces the other. Upgrading locks is worthwhile regardless of alarm status.
Take Action
Don’t wait for your lock to fail at the worst moment—or for someone to exploit its weaknesses. Walk through your property today and honestly assess each external lock using the signs above.
If two or more signs apply to any lock, replacement should be a priority rather than a someday project.