Burglar-Proofing Your Home

In order to deter and/or prevent break-ins, it is important to know what factors a burglar will take into account.

Burglars typically scope out a target first by examining doors. Basically, the strength or weakness of any door depends on three factors: the material the door is made of, the location of its hinges, and the kind of lock(s) used. If they discover a weakness, burglars will generally try to “defeat” locks and doors instead of forcing them open, since this is less likely to attract attention. But burglar-proof doors must be able to withstand brute force attacks as well as more sophisticated attacks aimed at the locks themselves.

Picture of rhode island home invasion

Let’s start with locks

Burglars try to defeat locks in three main ways: either by picking, bumping, or drilling them.

Lockpicking requires considerable skill and patience. The details are highly technical, but the basic idea is straightforward. Every lock contains an inner “plug” filled with a particular configuration of pins, which prevent a doorknob from turning and allowing the door to open. The purpose of a key is to move aside the pins in such a way as to allow the knob to turn. Someone who knows how to pick locks can manipulate the pins in the cylinder so the knob can be turned. For these reasons, burglar-proof locks contain certain features that make lockpicking a lot more complicated and time-consuming.

The second approach, lock bumping, is also widely used by burglars. Bumping requires the use of certain types of keys, which have been crafted specifically to engage the pin mechanisms inside locks. Once the key is inserted into the lock, it is possible to hit (or “bump”) the key itself, which in turn jolts the pins out of position and lets the knob turn.  Such bump keys are easily acquired by burglars, and can readily be used. For these reasons, it is essential to install locks that are bump-proof or at least bump-resistant.


Another method used is simply drilling out the entire core of a lock cylinder. Obviously, this eliminates the plug as well as the pins, so that there is no longer any obstacle to opening the door. This is much noisier than picking or bumping, however, and therefore it may not be the first choice for many burglars – depending on the location and visibility of the lock.

Good Locks

For the above reasons, two common mistakes made by homeowners are installing weak locks, or forgetting to put locks in vulnerable places.

With regard to the first issue, it generally pays to install “high-security” door locks (and padlocks). High-security locks are able to withstand lock picking, bumping, and drilling. Any good locksmith will be able to recommend preferred brands having these features.

Aside from the brand, the type of locking device is also very important. Deadbolts are generally favored because they can withstand a great deal of force. Likewise, mortise locks are strong and durable. A heavy-duty tubular deadbolt or mortise lock provides great protection if it has at least a one inch bolt.

One potential defense against lock picking, bumping and drilling is to install keyless entry systems, such as electronic locks. On the plus side, these new locks will not be vulnerable to traditional attacks, since if a lock does not have a keyway, then by definition it is cannot be picked, bumped or drilled. But that fact alone does not make them a better choice! Many keyless locks are made from weaker materials than traditional locks, which may make them targets for brute force attacks.

Finally, with regard to overlooking vulnerable spots, it is important to remember that even highly visible doors may be considered good targets if they have obvious weaknesses. An accomplished burglar can quickly defeat poor locks or flimsy doors. One particularly vulnerable location is the garage, especially if it is an attached garage with a door to the home. Consequently, if there is a door between the garage and the home, it should always have a deadbolt on it.

Sturdy Doors

At this point let’s set aside the issue of locks, and focus instead on doors themselves. After all, if the locks are high quality, then burglars can opt to simply kick down the door or otherwise force it open. In order to combat this threat, “burglar-proof doors” are doors that are built to withstand excessive force. A burglar can’t kick a door down if they can’t find its weak points, or if those weak points have been fortified!

There are few crucial factors that differentiate burglar-proof doors from regular, vulnerable doors. The first factor is the physical material from which the door is constructed: it should be strong enough to offer up resistance to brute force attacks.

Ideally, it should be a solid core door that cannot easily be kicked in or punctured. For this reason, it is a good idea to steer clear of hollow doors as well as doors with plywood or glass panels. (If a door does have glass panels, they should be reinforced with security glass film.) Some of the best materials for burglar proof doors are steel, solid core wood and fiberglass. It may also be wise to install door security bars as an added measure.

Aside from the door material, the other critical factors concern structural features of the doorway assembly: the frame, strike plate, and hinges. It is possible to enhance the security of these features greatly.

One way of reinforcing the strike plate is to install a “strike box.” A strike box is a kind of plate that includes a box-like component, which makes it much more force-resistant. In addition, an important factor is the length of the screws used to attach the strike plate (or box strike) to the door jamb. Instead of using half-inch or even one-inch screws, it is far preferable to use two-inch screws for this purpose.

A critical factor is the material and construction of the door frame. The door frame includes the jamb and stop. With regard to the jamb, if it is made only of wood, then it should be reinforced with galvanized steel strips. All door frames should also include stops, which anchor the door and prevent it from being taken off its hinges. And this raises yet another concern: the hinges themselves. The best hinges are those with crimped pins, safety studs and set screws threaded through. And positioning is important as well: doors with inward facing hinges are usually easier to kick in. Finally, as with the strike plate, using longer screws will help strengthen the hinges.

It is worth mentioning sliding glass doors as well, since in some respects these may also be targets of attack. Sliding doors should certainly have their own locks, but it is equally important to block their tracks with a solid piece of wood or metal. Reinforcing the glass with security film is another easy way to enhance security.

Supplemental Security

Surveillance cameras can be very helpful in reducing theft, simply because they make it much harder for a burglar to scope out weaknesses without being noticed. And of course, many burglars may prefer to avoid properties with cameras that could identify them. The benefits of such a camera may be significantly enhanced by alarms, and by off-site monitoring systems.

Secure all the windows within your home, even the ones that you think might be unlikely targets. Most burglars target windows that have shrubbery in front of them because it keeps them hidden from view. For much the same reason, having good exterior lighting (including motion detectors) may also be a useful deterrent.

The bottom line is that burglar-proofing your home involves thinking like a burglar. A number of steps may be taken to significantly increase your security. But certainly, high-quality doors and locks should be a priority for any homeowner.