The Security Of Deadbolt Locks.
You Absolutely Need Deadbolt Locks on all Your External Doors.
The most usual way to enter a home is through an external door, be that a
front door, back door, side door or a door through from the garage.
Doors are a very convenient design feature found in houses and
Unfortunately external doors are not only a convenient entry point
for homeowners and their families, but also for burglars and other
Naturally it is the unlocked door that is the most
convenient for an intruder, no effort, no noise, no sweat – just walk
Most of us realize that leaving an external door
unlocked is an open invitation, especially for the opportunist burglar,
so we do lock our doors.
But how secure are the locks that we use? There is little doubt that the most effective locks for external doors are deadbolt locks.
a spring latch type lock a deadbolt does not lock when the door is
pulled closed, it has to be physically locked by a key (or by a catch on
A deadbolt is easily recognized as it is, usually,
rectangular in shape and has a flat – not beveled – end.
It is not
spring loaded and usually throws 3/4″ to 1″ in to the strike plate, the
further in the better.
Most spring latches do not throw into the door frame, instead the
latch springs into a cup affixed to, but not set into, the frame.
types of locks can easily be forced, with a shoulder barge or a swift
kick. Bang! – the door is open.
Also, spring latches can be sprung open with a credit card or other flexible implement, (yes, just like you see in the movies.)
On the other hand, correctly installed
deadbolt door locks virtually can’t be sprung open, and it would take
the kick of an elephant to bust them open, that is why you absolutely
need deadbolt locks on all your external doors.
Single Cylinder or Double Cylinder?
With single cylinder deadbolt locks you use a key to lock and unlock
from the outside and a catch, or a knob, to lock and unlock on the
The obvious advantage is that you don’t have to hunt for the key
to open the door from the inside.
The disadvantage is that if
your door has glass panels, or there is glass near your door, a burglar
could break the glass, reach in, and unlock your door.
mail slot could be another problem, some burglars have been known to
insert a device, made from wire and cord, through the mail slot and use
it to operate the catch.
Double cylinder deadbolt door locks need to be locked and unlocked with the key both from the outside and the inside.
This means that even if a glass panel is broken the housebreaker is unable to get in without the key.
A key will need to be kept near the door, (but out of any possible reach
of a burglar) in case of emergency, particularly fire.
because double cylinder deadbolts may make it difficult to exit your
property in an emergency that some local building codes do not allow their use.
It may be possible for a burglar to slip a saw blade between the door
and the frame and saw his way through the deadbolt.
This would take
some time, but to make that job more difficult high security deadbolt
locks are available that have internal anti-saw pins. The pins spin
around with every stroke of the blade thus making the bolt very arduous
to hack through.
No doubt about it, deadbolt door locks
provide a high degree of security. But even the best locks fitted to a
poor standard of door will be a waste. Likewise a good door and lock
would be wasted in a weak frame.
Use high quality screws of at least 3″ to secure the strike plate/strike box into the frame.
Electronic deadbolts are available that are operated by a keypad, a remote and even Fingerprint Recognition Technology. However it is the deadbolt itself, and not the method of operation, that makes a deadbolt lock such a good deterrent against housebreakers.
Home Door Security
Deadbolt Door Locks.