Choosing a lock for the front door

Recommendation points

• What types of door locks are there
• And now in more detail about the design and types of door locks
• Crossbar lock
• Cylinder lock
• Suvald castle
• Electronic lock
• What is important to pay attention to when buying a castle
• What kind of locks are better to install on the front door?

Remember a fragment from Gaidai’s painting “The Diamond Hand” – when Lelik and Kozodoev stand in front of the Chief’s apartment after the failure of Operation Game? The chief carefully examines a couple of hapless jewelry thieves through the peephole, then with his hand, on whose finger a diamond in a gold ring sparkles, he begins to unlock all the latches, chains and locks – and finally, turning a decent-sized wheel, reminiscent of a lock of a large bank safe, opens the door. Comedy master Leonid Gaidai, of course, exaggerated the number and power of door locks, but on the whole he was completely right – it is the number, quality and type of locks that determines the resistance of a steel door to burglary.

A steel door, even of an impressive size, reinforced with thick steel sheets, with a box tightly connected to concrete or brick walls, but with weak locks of a typical design, will not resist an experienced burglar even for 10 minutes. In order not to find yourself in something like this situation – you returned home after a long absence, and your steel door is open and your valuables are gone – you need to carefully approach the issue of door locks.

What types of door locks are there

First, the following should be noted – each door lock, regardless of its type, must have a passport, in which the class of this lock must be indicated. Serial door locks can be from I to IV security class:

• Class I – such locks do not represent any obstacle for a burglar of any level, they will be opened in just 5-10 minutes;
• Class II – such locks are slightly more resistant to burglary: a novice will not open them, and an average burglar will take about 10-20 minutes;
• III and IV class – locks of these classes are suitable for installation on steel doors, they can be opened only by a professional, spending about 20-30 minutes for III class and at least half an hour for IV class. It is extremely difficult to open such locks, even using powerful electrical equipment and special devices..

And now in more detail about the design and types of door locks

Crossbar lock

A rack and pinion lock is the simplest type of lock, attaching a stretch to the I security class. You have probably come across this type of lock: a flat key, grooves cut at different angles on both edges; on the lock bolt there are the same grooves, falling into them, the key moves the bolt, unlocking or locking the door.

Often the rack and pinion lock (crossbar) is equipped with one / two handles for unlocking from the inside – they seem to be created for a burglar operating with a thin hollow tube and a loop of fishing line. Do not use such a lock for your front door, it is absolutely unsuitable – it can be opened without a key and a master key in 5 minutes!

Cylinder lock

Cylinder locks are widespread, and some of them can be opened with an ordinary pin, and for some it is extremely difficult to pick up a master key. However, a thief does not need to do this – just one / two strong blows on the “larva” of such a lock, it flies into the room, after which it is quite simple to open the lock. A distinctive feature of the cylinder lock is an English key, shaped like a flat mushroom, it has a hollow in the middle and cut out recesses on one side (keys with recesses instead of slots are slightly better).

I am sure you are familiar with such a castle. It can also be opened using a household door and a hardened drill bit: the burglar will connect the drill to the electrical panel on the staircase and drill the pins that form the lock code. The pins in most standard locks can be “removed” in another, less noisy way – a “roll” is used, similar to a key blank, but made of high alloy steel. “Convolution” is inserted into the keyhole, a lever is attached to it – the burglar makes several turns with a bunch of lever + “roll” and demolishes the pins made of softer metal. By the way, a cylinder lock can also be opened by a similar method (its key has an oblong round shape with recesses for pins). However, do not rush to abandon the installation of a cylindrical lock – you need to choose such a model, in the design of which additional protective elements are introduced: a sheet armor insert equipped with pressed hardened steel balls. Such a tab is extremely difficult to knock down and pull out, when trying to drill, the balls will not allow the drill to be installed, and the tab itself will rotate freely, preventing the drill from going inside the lock mechanism. Class III or IV cylinder lock with armored insert is the best choice for steel entrance door.

Suvald castle

The lever lock, invented in 1818 by the Englishman J. Chubb, is relevant to this day – its design uses plates (levers), lined up with key teeth (a long round rod with two or more plates at the end, special recesses are carved on the plates) into a given position , after which you can turn the locking mechanism.

Even if one of the levers does not accept the given position, the lock cannot be opened. Burglars can open such a lock only by picking keys. The security class of such a lock depends on the number of levers installed in it – the more there are and the higher the quality of the metal from which they are made, the better. As in the case of cylinder locks, armor plates greatly increase the resistance of a lever lock to a burglar. Locks of this type are well suited for the front door..

Electronic lock

Besides mechanical locks, there are electronic locks. A good electronic lock with a sufficient security class will be good especially because an ordinary burglar is not ready to face it – opening requires special skills and devices. The electronic lock does not have a metal key, it is opened by dialing a code, a remote control or a magnetic card.

By the way, I do not recommend using an electronic lock, which is unlocked by a fingerprint – it can be opened by providing the lock photocell with a photo of papillary lines from the owner’s finger. In general, electronic locks are good enough, but are not widely used due to their high cost..

What is important to pay attention to when buying a castle

Each lock must have a passport, issued in accordance with all the rules of the Russian Federation. Locks, in the passport of which the class from II to IV is indicated, must necessarily have a certificate of quality conformity (I class is not subject to mandatory certification). The three main components of any lock are reliability, strength (tested according to GOST 19091-82 and GOST 23306-86) and resistance to burglary attempts (tested according to the method of the Ministry of Internal Affairs of the Russian Federation). Carefully inspect the structure of the lock – there should be no rust stains.

The lock must be selected depending on the thickness of the steel sheets from which the door frame is assembled – if the metal thickness is less than 4 mm, there is no need to install a massive lock, because it can deform the door. Some owners of apartments / houses, in order to increase the level of security of their homes, install locks with long massive crossbars, sliding apart when locked in two / four directions at once. The weight of such locks and their crossbars, with frequent opening / closing, wears out both the lock and the door.

What kind of locks are better to install on the front door?

Lever locks will be the best in design – their mechanism is located inside the door frame, in order to break such a lock, you first need to get to the mechanism, and this is difficult. According to experts, it is necessary to install two locks (at least) of different types – a lever and a cylinder, equipped with at least three retractable crossbars, protected by armored inserts and having a class of at least III. You can install combined locks: in such locks, both mechanisms are used at once – both cylinder and lever, and the action of both systems can either complement each other (when you try to open one system, the second will lock itself), or work separately. It will be especially difficult for a burglar to open a combined lock – knowledge of both systems will be required, a separate set of “tools” for each lock system.

Last tip:there is no need to take out (light up) the keys to a new, recently installed lock in public – an experienced burglar does not need a mold from your key, he just needs to carefully examine it to make a duplicate and understand which system lock is on your front door.