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So far you’ve read all about different types of locks and cylinders you can have on your front door. But the story is far from finished! A secure front door needs more than just locks. Here we’ll go over a few additional door security items that you could install on your door.

London bar

Your Yale lock consists of two parts: the lock (fitted on the door itself) and the keep (fitted on the frame, into which the locking bolt goes). The keep is affixed to the door by just a few screws which, in theory, could be ripped out if someone applies enough force to the door.

A London bar is a strip of metal that goes up the length of the door frame, covering and thereby reinforcing the keep, so that it can no longer be ripped off. The pictures below show a tidily fitted London bar on a CISA electric lock.


Lockguards (pictured right) are a wonderful thing, used to reinforce your door. Lockguard While it’d take a lot of force to do so, it’s theoretically possible to smash your lock out of the door, say with a battering ram or similar. Lockguards sandwich your lock into the door, meaning that anybody keen on smashing the lock out of the door has to smash a huge chunk of wood out with it, plus a sandwich of steel.

In other words, using lockguards, you increase the level of force required to harm your lock. This acts both as reinforcement and as a deterrent. A miscreant who sees those on your door will likely go to the lower hanging fruit of your neighbour’s house.

Letterbox cowls and cages

One thing locksmiths can do to open your door is to reach through the letterbox using a tailor-made grab-arm, and to pull down any handle on the inside, in the hope that it’ll release the door. Most of the time, this works because many people (a) have only a Yale lock on the door or (b) didn’t lock their deadlock, even though they have it.

But just because a locksmith has a special tool to do it, doesn’t mean a burglar can’t get away with a less professional piece of equipment.

My neighbour occasionally slams his door shut, leaving his keys inside his flat. On the occasions where I haven’t had my tools to hand, I’ve got away with using a stick with a coat hanger tied to the end, and also a tennis racket.

A letterbox cowl (pictured right) is a sort of ‘hood’ Letterbox Cowl that you can put on the inside of your letterbox, to prevent anybody from reaching through. What it does is it forces anything going through the letterbox to go down first, before it can go up.

This works pretty darn well, since you’d need plenty of joints in your locksmith’s letterbox tool or coat hanger on a stick to get the door open. In practice, this is incredibly hard, if not impossible.

Alternatively, some people like to install a proper box or a cage behind their letterbox. This blocks access to the inside of the door entirely, being instead just a sort of bin for mail to drop in. The homeowner can then, at their leisure, open the box from the inside using a key.

Both solutions allow you to keep your door secure without in any way impeding the task of the postman.

Rack bolts

Rack bolts are common locks that can add extra protection to a door. They’re small bolts that are easy to fit and usually go on the inside of a door only. In other words, the key-hole is not accessible from the outside. Why is this so important? Because rack bolts pretty much all use the same key.

Rackbolt Key

This type of rackbolt key is probably a familiar sight to many readers.

They’re cheaper than fitting a full deadlock and they shore up the security on the top and bottom of the door. It’s not advisable to use them instead of an additional deadlock, but you can use them on top of a deadlock.

Since they can only be accessed from inside, there’s an inherent lock-out risk. For instance, if your flatmate has locked the rack bolts from the inside and has gone to bed already, you can’t get in from the outside without them letting you in.

For this reason, many people choose to use rack bolts as an easy way to reinforce a back door or patio door rather than a main entrance door.

Door chain and spy-hole

These are types of secondary security product. Having them on your door doesn’t make it harder to break in, but it gives you more control over whom you let in.

A door chain is literally just a chain that connects the lock-side of the door with the frame, which prevents the door from opening more than about 15cm. This allows you to see who is standing outside before you choose to let them in.

A spy-hole serves a similar purpose. It’s a little lens through which you can see who is standing outside, without needing to open the door even a crack.

Both products are useful for people who have a lot of unsolicited callers, or who are concerned about whom they open the door to.

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