Euro profile locks - a few tips

Test door, lock sticks out a bit!
Euro profile locks are a doddle to change - it is literally one screw, and you can slide out the old lock and slide in the new locks. They are easy to buy, or order on-line. But a few quick tips:

  • You need to order the right size (inside and outside). This is the distance from the centre of the lock to the key slot each side. Usually available in 5mm steps. You want it just right, not sticking out, though good locks have a snap off part if someone does take pliers to it.
  • You can order keyed alike locks so they all have the same key, which can be very handy. Somehow people don't realise this!
  • There are loads of different quality and prices of locks.
  • You can have key both sides, or one side with a thumb turn, or just keyed one side and blank the other side even (half lock).

So, when we moved in, the first thing I did on day 1 was order new locks. Five of them. The house had all been recently re-done and the locks in the house already were all brand new, so a bit of a shame. But I wanted higher quality locks and did not want five different sets of keys (don't people know you can get locks that have the same key?).

Cheaper lock

I ordered like for like, the same size, and keyed both sides as that was what was in the house.

Unfortunately, after a little while we realised the choice of locks was wrong. You do not want keyed both sides. The reason is that the doors were all multipoint locks, and only locked by turning the key. Without that someone can literally walk in from the street (which has happened!). But this means you can only use the door from the inside if you have a key to unlock it. This means if there was a fire in the night when the doors are (obviously) locked, you need a key to get out. Remember the house originally had 5 sets of keys so you need to find the right key for the door by which you are trying to escape from a fire.

The short term fix, a key on a hook by the door, but that is far from ideal. Obviously.

Thumb turn on inside
So I ordered another complete set of locks (getting expensive now) with thumb turn on the inside. This means you can always lock or unlock the door easily from the inside without a key. Importantly it is not hard to unlock if trying to escape a fire. I actually disposed of the first set of locks as no use to me any more.

As some of you know, I have a complete door access control system and alarm system, but changing locks means a locksmith and time and money, so even though we have been here over a year I had not yet changed the locks. I was also researching the right lock for the job. Being a house, I really don't want an "exit button" and an "emergency break glass" by every door. I also wanted a "fail secure" so a power cut when we are away (long enough for battery to drain) does not leave all the doors unlocked. But I also want it "safe" so always possible to get out in a fire even when nothing is working electrically.

So the locks are Abloy EL560. I have been testing on my office/study door, meaning we now have six locks. This is great, it is fail secure (i.e. power fail is locked). But it can always be opened from the inside with the handle, and with a key. It also has signals so you know if opened by handle or key. This is great.

RFID reader
They are being installed in the rest of the house shortly, with my AES DESFire based readers to open from outside - nice and secure, and all links in to the alarm system.

However, if it was to be opened from outside using a key, I would want the alarm to know this, and disarm. The idea is we can trust a key. That is fine, I simply configure the system to disarm when the key is used. The system is very flexible and easy to configure for various types of lock.

Except... I have thumb turns on the locks on the inside. I don't need these now as you can open the door with the inside handle. But if I set the system to trust a key it trusts the thumb turn as well. Someone breaking in only has to turn the thumb turn on any door to disarm the alarm. So yes, obviously, it is not being configured to do that (yet). Indeed, one approach would be you have to enter a PIN on the keypad if not using a DESFire fob, even if you did use a key. Given how easily keys, even high security keys, can be copied or 3D printed, this may be sensible anyway.

The real answer is order locks keyed both sides, or even no key at all on the inside now.

I had a full set of locks just like that from when we first moved in. I have disposed of them. Arg! So another set of locks, six this time.

The moral is never throw anything away, ever!... I should know this already.


  1. After building an extension with 2 new external doors I replaced all the Euro profile cylinders, a traditional cylinder barrel and, added, a pin padlock (for the driveway gate) with Mul-T-Lock parts, all keyed alike. I carried only two keys, the car and the house.
    Those Abloy EL560s are serious money but a very 'nice' solution.

  2. I don't like the "Alarm disarms by itself" approach as if someone steals my keys they can get in without the alarm going off, dislike keyfob based alarm systems for the same reason... prefer to stick to "Something you have and something you know"...

    1. Indeed, the "alarm off on key" is looking less and less of a good idea to be honest. If a key is lost then you have to change all the locks. The fobs are a lot better as they can be individually black listed - and I can do that from my phone when not at the house even, if I lose my fob.

    2. You could use the "opened with key" signal to set up a different grace period for the pin entry or something perhaps?

  3. I'd be very careful when changing locks or methods of accessing a property. Check the wording in the insurance policy. Some policies are very prescriptive about the type of lock.

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  5. Most of the Euro profile cylinders on the market are complete crap.

    There's only about three or four which aren't trivially easy to bump open, snap the cylinder or extract entirely with the right tools (which can be bought on fleabay for a few quid).

    Few years ago a neighbour got robbed - insurance wouldn't pay out at first as the burglars bumped the lock open, fortunately someone else made a statement to plod saying they saw someone acting suspiciously at the back of a house two doors down. I had a bit of a google and with 30-40 mins practice I could bump all of our doors open inside a couple of minutes with no damage to the door or lock, just needed a small hammer and a "bump key" (fleabay, £1.99 at the time).

    The locks which are somewhat more resilient use magnetic pins in the mechanism and magnetic contacts on the keys. They can still be defeated however it will take more planning/effort/cost on the part of the burglar & its a lot more likely they'll leave signs of attempted/actual entry.

    You get what you pay for with Euro profile locks - decent ones start at about £35-40 retail.

  6. Yes, search on YouTube for "lock snapping" and make sure all your Euro locks are fitted flush with the outside surface of the door to reduce the attack surface.

    And don't get me started on uPVC front doors which can be kicked through in seconds. Again, do a YouTube search.

  7. Not relevant to you now, but for anyone else in a similar position, when I moved in to my house I discovered the lock in the door actually had the right mechanics to allow for a split handle setup, so the front would only operate the multi-point locking part, you'd still need the key to do the final release (i.e. the door can be unlocked such that from inside you just use the handle, but you still need the key from outside).

    All I had to do was measure the lock to work out which profile it was, and then order an appropriate set of split handles to replace the existing in-line ones (a few tens of pounds I think), rather than ripping out the entire mechanism - so worth checking if you're in a similar position...

  8. I want different things from my locks depending on whether anyone is at home and whether it is night or day:
    * When everyone is out, a key should be required to open the door from both inside and outside.
    * When someone is in they should be able to open the door from the inside without needing a key.
    * If I go outside I want a choice of whether the door locks itself when I close it so that I don't necessarily have to use a key to get back in from the garden.
    * At night it should not be possible to open the door from outside, even with a key.
    All of this was easily achievable at a previous house with a wooden/composite door fitted with a good quality Yale style lock as well as a multi-point lock, but unfortunately is not possible with the ubiquitous uPVC door. Is it unreasonable to demand these things?


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