Home Security: Securing Doors

By Ira A. Lipman

The easiest way for someone to enter your home is simply to open an unlocked door. In fact, this is the way that many houses are illegally entered. Very few families take the number one precaution of locking exterior doors at all times, whether someone is at home or not. Children who are in and out of the house all day leave doors unlocked, as do people who step next door for a neighborly visit.

An example will illustrate just how hazardous an unlocked door can be. A woman was in her house, not particularly concerned that her back door was unlocked, since she had a large dog in whose presence she felt absolutely secure. Sure enough, an intruder entered through the unlocked, and sure enough, the dog sprang to the attack, badly mauling the intruder. Unfortunately, the intruder was a two-year-old who lived next door.

While doors should always be locked, this in itself is actually small defense against the determined criminal. Hereï¿½s why:
ï¿½ Doors often have small glass or light plywood panels, which can easily be broken or cut with a rasp or a keyhole saw. Someone could then open the lock very easily by simply reaching through the hole.
ï¿½ A door that doesn't fit its frame properly can easily be forced open by wedging a tire tool or prying bar between it and the frame and then " spreading" the door away until the bolt moves free from the strike (the hole in the door frame that the bolt slides into when the door is locked).
ï¿½ Some older homes and apartments have doors that open outward. These can often be opened simply by removing the hinge pins and lifting the entire door from the frame. The Multi-Lock, mentioned later in this chapter, is useful in protecting doors of this type.
ï¿½ Certain locks can be easily picked, removed, or destroyed.

It is virtually impossible to prevent someone from entering your home through an outside door if that person is really determined to do so and has enough time and skill to accomplish the deed.

If you can't entirely eliminate the possibility of someone's break into your home, then what' the next best thing to do? Make breaking in as difficult and as time-consuming as possible. And if the burglar still succeeds, at least you will have forced him or her to destroy the lock or part of the door, or in some other way to leave clear evidence of illegal entry. This will be very important when you file an insurance claim to recover your loss. If nothing else, it will at least minimize the likelihood of your claim's being denied on the grounds of negligence.

Strengthening Doors

Strengthening doors ï¿½ and these comments apply to all outside door - is not difficult. First, the door itself should be as sturdy as possible. A hollow-core metal or solid wooden door is best.

For aesthetic purposes, however, many prefer doors with heavy glass or wooden panels. These types of doors offer considerably less protection than those just mentioned, but there is one thing in particular that you can do to make them more secure: double-cylinder locks should always be installed on such a door. This kind of lock requires a key to open it from the inside as well as from the outside, which prevents an intruder from unlatching the lock by reaching through broken glass or a hole in a wooden panel. That much delay ï¿½ unless the burglar is especially determined ï¿½ will very often send an intruder of f to easier pickings. A word of caution, however: in the event of fire or other emergency double-cylinder locks can delay occupants from getting out of the house. Consequently, a key to the in side lock should always be kept conveniently at hand.

There may be a reason why one of these measures won't be practical. For example, your landlord might not want to replace an existing door or permit you to do so, or you, as a tenant, might not want to go to the expense of installing a really good door on someone elseï¿½s property. It may not be a thing of beauty, but it might save your TV, DVD, etc.

In securing all outside doors, be particularly meticulous with those that offer an intruder cover ï¿½ such as doors inside vestibules or enclosed porches. Here a criminal could work at leisure, safe from observation by neighbors or passersby. Be aware that these protected areas often are of less sturdy construction than other parts of your home. Ideally they should be finished off with exterior walls as sound as the rest of the house.

Every exterior door should fit its frame snugly. Most don't. House-builders sometimes take shortcuts by making the openings oversized, and even a well-fitted door can develop problems as a house settles on its foundation. The best way to remedy a poor fit is to reinforce the door frame or to replace the door with one that fits. If you don't want to go to that much expense, at least use locks with bolts that slide a minimum of one inch into the frame, or attach a common thumb lock with a long bolt to the inside face of the door. Or better yet, ask a locksmith about an L-shaped metal strip that can be attached to a door frame to protect an inward-swinging door from being jimmied with a crowbar. A flat plate attached to an outward-swinging door can be used to cover such an opening, but it should be attached with flat bolts or non-retractable screws so that it cannot be removed from the outside.

An L-shaped metal strip makes door jimmy-proof

Storm doors are excellent energy savers, and when equipped with adequate locking devices, they add an element of security by introducing an additional delay factor. The glass and/or wrought-iron features serve as another deterrent.

Chain Locks

In general, chain locks are not effective in preventing someone from entering your home. A good kick might easily pull the lock away from the wall. Furthermore, the chain itself can be cut with a hacksaw or a bolt cutter. To maximize the effectiveness of such locks, anchor them with long screws or, better yet, bolts. A wedge-shaped rubber doorstop inserted beneath a door can add substantial additional protection against unwanted entry.

One advantage of a chain lock is that, when it is engaged, it indicates to a burglar that someone is at home, generally causing the burglar to move on. One distinct disadvantage of a chain lock is that a burglar, once inside your house, can become relatively free from being surprised on the job simply by engaging the lock him- or herself.

The value of a chain lock is thus debatable, but on balance a good one is worthwhile, if for no other reason than its effect of delaying entry into your house. Also, if you have solid doors without peepholes, a chain lock allows you to speak to visitors without fully opening the door.

Peepholes

A solid exterior door should be equipped with a peephole (or interviewer or optical viewing device) simply to allow you to ascertain who is outside before you open your door. Ideally, the peephole should have a wide-angle lens. If at all practical, a convex mirror should be installed opposite the door. With this device, you should be able to see anyone attempting to hide beyond the vision range of the peephole.

Night Latches and Doorknob Locks

The night latch or rim spring latch commonly found in most older houses, and the cylindrical lock or lock-in-knob found in many apartments and newer houses, do not offer a great deal of security. The lock-in device is easily defeated by prying the entire assemblage loose with a crowbar. Night latches are very common because they are inexpensive and convenient and because they can be engaged simply by slamming the door shut. But often they can be opened by sliding a credit card or similar piece of plastic into the gap between the door and the frame.

Newer night latches have protection to prevent the ï¿½credit cardï¿½ entry into a structure. This represents little, if any protection, however, as doors of this type can often be compromised by forcing them open with a screwdriver. This can be prevented by equipping the lock with an effective dead-latch plunger, which prevents pushing back the latchï¿½s beveled edge. Unfortunately, the faceplate can be pried loose and the cylinder removed quite easily. Thus, this type of lock isnï¿½t considered a satisfactory locking device.

Dead Bolt Locks

The remedy for these problems is a dead-bolt lock. Such a lock usually features a square-faced (rather than beveled) bolt, which is engaged from the inside by the second turn of a key, or else is operated by turning a thumb knob. Unquestionably, the dead bolt is superior to the common night latch inasmuch as it cannot be forced open with a knife blade, spatula, or similar implement. The shape of the bolt and the pressure required to move it in any way other than through the normal use of a key or knob make these burglar tools useless. If the bolt is long enough (a one-inch throw is recommended), the door becomes most difficult to jimmy open. Either a variation on this theme, the rim- or surface-mounted vertical dead-bolt lock, or the ring-and-bar lock is an even more effective protection measure. For high-risk applications, the Multi-Lock is a dead-bolt lock that, when engaged, bolts into all four edges of the door frame.

Dead bolts. A dead bolt lock is your best security buy

A dead bolt is, dollar for dollar, the best means of defense that you can enlist in securing your home. You definitely should install one on each outside door either in place of or supplementary to whatever locking devices you are now using. A number of excellent dead-bolt locks are on the market.

Other Locking Devices

There are a number of virtually pickproof locks available, but they are expensive and, except in the most extraordinary of circumstances, unnecessary for the average homeowner. Few burglars are skilled at picking locks, so unless there are items of unusual value in your home, installing pickproof locks generally would constitute overprotection.
Push-button combination types of locks are also generally available and are secure from lock pickers, but a drawback is that the combination can be "read" even from great distances. Such locks are therefore much more effective for interior security than for exterior use.

No lock can prevent a door from being opened through the application of brute force, especially if there is a weak door frame. The wooden door frame itself can present a problem. In many cases when a forced entry is made through a door, the dead bolt itself has held but the door frame around the strike plate has splintered. This can be overcome by ensuring that there is proper bracing in the wall behind the door frame. If you push against the door frame on the strike-jamb side and it bends outward, it is not well supported.

The proper combination for preventing the wooden door frame from splintering without determined attack is by using a high security strike box or plate and screws long enough to anchor the strike device into two-by-fours bracing in the wall immediately behind the strike device. A police brace, a long steel bar that reaches from the floor to the door at an angle, serves as an effective anti-intrusion device in much the same way as does wedging a piece of furniture under a doorknob. The top edge of the bar fits into a lock mechanism installed on the door, and the bottom fits into a metal socket in the floor. Another version of the police brace is a horizontal steel bar that is mounted across the center of the door. This fits jamb braces attached to both sides of the door frame. It can be removed or put back in place in a few seconds. Of course, these devices can be used only when you are on the inside. They do, however, have the very real advantage of being completely pickproof.

Another type of device favored for a high level of home security is tubular keyway lock. You have almost certainly seen the round locks found on many vending machines. Perhaps you have even seen the service person open the vending machine, using a small cylindrical key. This locking device has the advantage of being extremely difficult to pick and, for all intents and purposes, impossible to force open with a screwdriver or wrench. Other locks have similar advantages, and the configurations of the various available locking devices are many.

Sliding Doors

Of all the doors giving access to your house, probable the most hazardous are the patio doors ï¿½ typically of the sliding-glass type. In general, such doors have locks that are none too effective. Even if they hold up against an intruder, a piece of glass can easily be cut or broken from the doors and the locks disengaged.

One safeguard is to attach locks with vertical bolts that fit into holes in the floor and upper frame and hold the door in place when it is engaged. Another safeguard is to substitute the panes of plate or tempered glass with polycarbonate or other shatterproof glass, or other types of impact-resistant glazing material. An inexpensive auxiliary means of securing such doors is to cut a broom handle to fit the track in which the doors slide. Thus, even if the lock were forced, the door would not slide open.

These highly susceptible openings into your home may be further protected by inserting screws into the upper track of the door assemblies. Properly placed, these screws can prevent the lifting and removal of an entire door, glass, frame, and all.

A broom handle cut to size helps secure sliding doors

Garages and Outbuildings

Garage doors that lead directly into the house are, in fact, entry doors, in the same way as the front door. However, they represent a more serious threat to your security, because an intruder, hidden from sight in the garage, could leisurely breach your security and attack your assets or your family. At the very least, such an opening should be protected by a solid-core door, a dead-bolt lock, secure hinges and, if warranted, an intrusion alarm. Obviously, you should keep your garage locked shut whenever practical. A ten-minute trip to the grocery could result in an intruderï¿½s use of your unprotected ladder to gain access to a substantially more unprotected upstairs nursery.

All garages should be protected with good padlocks. A good padlock has a hardened (or, better yet, a stainless) steel shackle (the loop). This should be no less than 9/32 inch in diameter. It should have a double locking mechanism (heel and toe), a five-pin tumbler, and a key-retaining feature. This last feature, sometimes difficult to find, prevents you from removing the key unless the lock is engaged. Cane bolts and sliding hasps, installed on the inside, are inexpensive but highly effective means to increase the security of your garage.

Roll-up garage doors require two good padlocks for acceptable security, one on either side of the door. Sometimes upward pressure on one side of the door will cause the other side to rise enough for someone to crawl under. Many garage door assemblies, electric or mechanical, have predrilled holes on the tracks for a padlock, which, of course substantially increase your safety and perhaps your peace of mind.

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