Guide to Deadbolt Locks
- The most common form of deadbolt lock is the single cylinder deadbolt lock. From the outside of the door, a key must be inserted into the lock to slide the bolt forward into the door frame (thereby locking your door) or sliding the bolt back into the door (thereby unlocking the door). On the inside, a latch may be thrown, which slides the bolt back and forth (depending on whether you locking or unlocking the door).
The advantages of a single deadbolt lock are that it is generally affordable and will leave your door secure when locked. Ensure the bolt extends out of the door edge by at least 1 inch. Longer bolts make prying the door frame open more difficult. - A double cylinder deadbolt differs from a single cylinder deadbolt in that you need a key to lock and unlock the deadbolt from both sides of the door. In other words, there is no latch on the inside of the door that makes locking and unlocking door easier. Use this type of lock on exterior doors that have glass windows. If your door has glass windows, a burglar may break the window in an effort to throw the latch on the door. If the door is a single cylinder deadbolt, the burglar will easily be able to gain entry into your home by breaking the glass and turning the latch. If the door is a double cylinder deadbolt, the burglar must have a key to open the lock, whether from the inside or the outside.
Note that double cylinder locks may also be dangerous. For instance, should an intruder break into your home, or should an emergency occur (such as a fire), your family may need to exit the home quickly. If the door has a double cylinder deadbolt installed, you may lose precious seconds searching for the key. Keep this in mind when choosing whether to install this type of lock. - Finally, you may choose a keyless entry deadbolt lock. This lock is more expensive than the previous examples. The lock is locked or unlocked by punching in a keycode. Keyless entry deadbolts have the advantage of being convenient: some have a remote entry option, and punching a keypad can be faster than fumbling for a key and inserting it into the keyhole. Note, however, that keyless entry deadbolts are not always waterproof. This could cause the lock to malfunction if it is exposed to excessive moisture.