Good locks are the first line of defense against intruders. They are a real deterrent because burglars choose the easiest places to break into and avoid those that take longer.
Locks range from bad to excellent as far as protection goes. It's important to make sure you know which locks are best and what they do. Below, we describe key-in-the-knob locks, deadbolt locks, and keyless locks.
When used alone, these types of locks offer very limited security. Depending on the quality of the lock, extra force on the knob can defeat the lock. They are usually not pick-resistant and the keys can be easily duplicated. This lock has two kinds of latches: the spring latch and the deadlocking latch.
The bolt is spring operated so it can be unlocked using a piece of plastic (credit card), thin metal, or wire between the door and frame. The bolt can also be held back by tape and the hole in the striker can be stuffed with wadding, making this lock inoperable.
This works the same as the a spring latch, except when the door is shut the latch becomes "dead". The spring action is blocked by a lever. However, very little force may be needed to move the bolt out of the striker.
The deadbolt gets its name from the fact that is does not move except with a key or thumb turn. It can't be moved with a credit card or tool because it does not have a spring. You can not lock a deadbolt and pull the door shut. You must turn the key or thumb turn to lock after shutting the door.
This lock utilizes one key and one thumb turn to operate. The exterior of the lock is usually controlled by the key and the interior by the thumb turn. This type of lock can be opened without a key from inside the residence. If this lock is located near glass, the glass can be broken and a person looking to make entry, can reach in and turn the thumb turn, unlocking your door.
This type of lock utilizes one key to operate both the interior and exterior of the lock. This type of lock allows the key to be removed from the lock itself. Caution needs to be used when using this type of lock. Although this type of lock is required for the homeowners insurance deduction, home owners should understand that this system can not be unlocked without the key. It is imperative the key be somewhere for quick access in the event of an emergency and fire. The good feature about this lock is that is someone were to make entry into your residence they could exit through a door and would be forced back out the way they entered. This limits the amount of property they can take in the event of a burglary.
This type of lock was developed for the reason of fire safty. On the outside it is locked by a key. On the inside it is locked by a thumb turn that is also a removable key. The thumb turn can only be removed when the outside key is turned to a certain position. The thumb turn stays in place when people are in the home. When the home is empty, the thumb turnkey can be removed and a burglar can't unlock by reaching inside. Children can't remove the thumb turn as they could a normal key.
The bolt should be no less than 1" when fully extended and some of it should still be in the lock for strength at that end.
The outside collar (around the cylinder where the key goes in) should be strong metal, not easily crushed or ripped open. If the collar rotates freely, it keeps the cylinder from being twisted off with vice grips or a pipe wrench.
A strong strike plate should be attached to the door frame to provide a strong anchor for the bolt to sit in.
Extended strike plates are available from locksmiths in 8" or 12" sizes and provide a stronger housing for a good deadbolt.
Use 3" to 4" wood screws when installing any strike plate, to go through the door frame and into the wall stud. Do not use drywall screws.
There are many variations of keyless locks available for homes, garages and businesses. They offer combination buttons, electronic or digital means of unlocking the door. Check with your local locksmith or hardware store for the latest developments.