Many people invest in security doors and then leave a cheap cylinder lock inside – one that can be picked in 30 seconds. The cylinder is actually the most important part of the lock, and also the most underestimated.
What Is a Cylinder Lock and Why Does It Matter
The cylinder is the mechanism inside the lock body where you insert your key. Without it you can’t open the door – but with a cheap cylinder you’re still not safe, because an experienced burglar can bypass it without a key.
Methods burglars use:
- Bumping – a special key and a small hammer can open standard pin tumbler cylinders in seconds
- Drilling – cheap cylinders without drill protection can be drilled out
- Pulling – a short cylinder can be gripped with pliers and yanked out
Security Classes (Resistance Grades)
Cylinders are classified under European standard EN 1303 into grades 1–6:
| Grade | Resistance | Typical Use |
|---|---|---|
| 1–2 | Basic | Internal doors, storage rooms |
| 3 | Medium | Flat entrance doors – minimum |
| 4 | High | Recommended for front doors |
| 5–6 | Very high | Banks, secure rooms |
For a flat or house front door I recommend at least Grade 4.
What to Look For When Choosing
1. Anti-Bump and Anti-Drill Protection
Look for cylinders marked:
- Anti-bump – specially shaped pins that resist bumping attacks
- Anti-drill – steel or carbide elements that prevent drilling
2. Cylinder Length
The cylinder must fit your door precisely. A cylinder that is too short can be gripped from outside with pliers and pulled out – this is a critical security risk.
How to measure: remove the cylinder (loosen the small screw in the middle of the lock face) and measure each side from the centre (e.g. 35/45 mm).
3. Number of Keys and Security Card
Every reputable cylinder comes with a security card (certificate), without which no copy of the key can be made. Keep it in a safe place.
4. Brand and Certification
Recommended brands: FAB, EVVA, KABA, Mul-T-Lock, ASSA. Avoid unbranded cylinders from supermarkets at £5–10 – the saving is not worth it.
Replacing the Cylinder
Replacement is a quick job – a handy DIYer or even a beginner can manage:
- Open the door and leave it open
- Insert the key and turn about 10–15 degrees (releases the retaining clip)
- Loosen the small screw inside the lock face plate
- Pull out the old cylinder
- Insert the new one in the same position
- Tighten the screw
- Test with the key
The whole replacement takes 5–10 minutes. If the cylinder won’t come out, the problem is usually the length or type of lock body – call a professional.
How Much Does a Good Cylinder Cost?
| Category | Cylinder Price |
|---|---|
| Cheap (not recommended) | CZK 100–300 |
| Mid-range (Grade 3) | CZK 400–800 |
| Good (Grade 4) | CZK 800–1,800 |
| Premium (Grade 5+) | CZK 2,000–5,000 |
Installation by me: the labour for a cylinder swap usually works out to 30–60 minutes. I’m happy to advise on cylinder selection on the spot.
When Should You Replace Your Cylinder?
- You’ve moved into a new flat or house
- You’ve lost your keys
- You’ve ended a tenancy or a relationship (an ex-partner had a key)
- The cylinder is 10–15 years old
- The key is starting to stick or is harder to insert
Door security is not the place to cut corners. A good cylinder costs CZK 1,000–2,000 and lasts 15 years. That’s a worthwhile investment.
Want to replace a cylinder lock or get advice on which one to choose? Call or message me – I’ll come, advise, and fit it.