Replacing a cylinder lock: complete explanation, step-by-step plan, and tips
Create a replace cylinder lock is a simple job that you usually complete yourself within 5 minutes — without a locksmith and without damaging the door. You remove the retaining screw, turn the key to release the cylinder, remove the old cylinder from the door, and install a new one. The most important thing is that you the correct size cylinder chooses and a secure SKG★★★ cylinder lock used, so that your door is immediately optimally secured again.
View our range now cylinder locks, measure your old cylinder with our measurement instructions or configure your cylinder via the order tool.
Video: replacing and measuring a cylinder lock
What do you need?
Replacing a cylinder lock requires few tools. In the vast majority of cases, you will only need:
- Create a screwdriver (usually Phillips head PH2) to loosen the locking screw;
- De corresponding key of the old cylinder;
- Create a new cylinder in the correct size — determine this before you begin;
- Possibly a tape measure or ruler to measure the old cylinder.
Tip: buy the new cylinder before you remove the old one, so that your door is never left unsecured.
Step-by-step plan for replacing a cylinder lock in 5 steps
Measure from the center of the screw hole to the outside and to the inside. This determines the size, for example 30/30 or 30/45. You need this measurement to order exactly the right replacement cylinder. Are you unsure? View our explanation on measuring a cylinder lock.
Open the door and locate the retaining screw on the narrow side of the door, level with the lock (below the cylinder). Loosen this screw completely with a screwdriver and set it aside. This is the only screw holding the cylinder in place.
Insert the key into the lock and turn it a small amount (about 15 degrees) to the left or right. This aligns the lug in the cylinder with the housing, allowing you to pull the cylinder out. Doesn't it come out immediately? Wiggle the key slightly while you pull.
Insert the new cylinder into the door in the same position, with the key lightly turned. The long side should be on the outside, and the knob or short side on the inside. Push it in fully until the screw hole of the cylinder aligns exactly with that of the door.
Tighten the retaining screw again — not too tightly, so that the cylinder does not jam. Then test with both the door open and closed to see if the key turns smoothly and if the deadbolt and latch work properly. Done: your door is securely locked again.
Determining the correct cylinder size
The size of a cylinder is measured from the center of the screw hole to the left and to the right, in millimeters. A cylinder with the size 30/40 is therefore 30 mm on one side and 40 mm on the other. Important: the cylinder must be on the outside. protrude a maximum of 3 mm relative to the fitting. If the cylinder protrudes further, it is more susceptible to core pulling — a commonly used burglary method.
If in doubt, choose a slightly shorter rather than a longer cylinder, and always combine a good cylinder with robust security hardware with core pull protectionThis is how you get the maximum level of security out of your door.
Which replacement cylinder do you choose?
When replacing, you determine not only the size but also the type of cylinder. The right choice depends on the door and your preferences:
Double cylinder
Operated with a key on both sides. The standard choice for most front doors. View our SKG★★★ cylinder locks.
Knob cylinder
On the inside, a rotary knob instead of a keyhole — handy for quick opening without a key. See the knob cylinders.
Identical cylinders
Open multiple doors with one key. Ideal for front door, back door, and shed. View keyed-alike cylinder locks.
When replacing, always pay attention to the SKG quality mark. SKG★ is the basis, SKG★★ offers more resistance and SKG★★★ is the highest level — with core pull protection, drill protection and anti-manipulation. Insurers and the police (Police Quality Mark for Safe Living) recommend a minimum of SKG★★ for exterior doors. All our M&C cylinders comply with SKG★★★.
Common mistakes when replacing
- Ordering the wrong size. Always measure before purchasing — an overly long cylinder protrudes and is vulnerable to burglary.
- Overtightening the locking screw. This can cause the key to turn stiffly or jam.
- Choosing a cheap cylinder without a quality mark. Without SKG, you lack core pulling and drill protection.
- Replace only the cylinder in case of weak fitting. A strong cylinder in poor fittings remains vulnerable; replace them together.
Replace it yourself or call a locksmith?
In most cases, you can easily replace a cylinder lock yourself: it is a job that takes just a few minutes. However, do call in a locksmith if the key has broken off in the lock, if the cylinder is seized due to wear, or if it involves a multi-point lock or a special type of door. If you know the size and type, you can order the correct cylinder from us and save on the installation costs of a locksmith (often €50 to €100).
Frequently asked questions about replacing cylinder locks
1. When should I replace a cylinder lock?
Replacing a cylinder lock is advisable in several situations. Consider moving house, lost or stolen keys, or when the lock is older than approximately 10 years. Replacement is also highly recommended if your current cylinder does not have an SKG quality mark. Modern cylinder locks offer significantly better protection against burglary methods such as core pulling, drilling, and manipulation.
2. Can I replace a cylinder lock myself?
Yes, in most cases you can easily replace a cylinder lock yourself without technical knowledge. It is a quick job where you only remove the retaining screw, loosen the cylinder with the key, and install a new one. However, it is important to choose the correct size and work carefully so that the cylinder fits properly and does not protrude. With a good step-by-step plan, this often takes less than 5 minutes.
3. How much does it cost to replace a cylinder lock?
The cost of replacing a cylinder lock depends on the chosen cylinder. For a standard cylinder, prices usually range between €30 and €100. If you opt for a high-quality SKG 3-star cylinder with core pull protection, the price will be higher. If you have the lock replaced by a locksmith, installation costs will be added, often between €50 and €100 extra.
4. How do I determine the correct size cylinder lock?
You determine the correct size by measuring from the center of the screw hole to both sides of the cylinder. This results in a size such as 30/30 or 30/45. It is important that the cylinder protrudes no more than 3 mm on the outside. A cylinder that is too long makes the lock vulnerable to burglary, while a cylinder that is too short will not function properly.
5. What is the safest cylinder lock?
The safest cylinder lock is an SKG 3-star cylinder with core pull protection. These cylinders have been extensively tested and offer maximum resistance against modern burglary methods such as core pulling, drilling, and manipulation. In the Netherlands, this type of cylinder is considered the standard for exterior doors and is often recommended by insurers and security experts.
6. Can I open multiple doors with one key?
Yes, this is possible with keyed-alike cylinders. In this system, multiple cylinders are manufactured so that they can all be opened with the same key. This is ideal for homes with multiple doors, such as a front and back door, a shed, or a garage. It increases ease of use without compromising on security.