Every person is very much concern about the security of his or her residence. They use to defend anykind of theft or sabotage by locking the door of their house. So door security is the most priority for us.

Door security involves mainly burglaries or theft related to the doors. Such break ins may take place atvarious places like front or back door, side etc.

Common residential door security includes door alarms, deadbolt locks, door chains etc. but amongst all of these systems the deadbolt locking system is one of the most efficient techniques employed now a day. It is quite distinct from the spring bolt locking system by some mechanism. It uses a cylinder that cannot be moved to the open position unless the cylinder is rotated. A deadbolt lock offers a good door resistance as it can only opened with the right key only. No other means can be applied to open it. It is often used as the complementary to the spring bolt lock at the main entrance door of the building.


There several types of deadbolt lock available in the market. First one is the single cylinder dead boltlock. It can be operated from the both side of the door but the locking mechanism is facilitated at onlyone side. The other side is only to open the lock by twisting the knob there. Coming to the next varietyof deadbolt lock is the double cylinder deadbolts. These are customized to accept the key from both sideof the door. A single key will operate at the both side. They usually lack the twisting knob. As they don’t require it. It prevents unwanted unlocking of the door. Some of the dead bolt lock contains a lockable knob. That is a key is always needed to open the door. A problem for the single cylinder deadbolt lock is the unwanted locking. As the lock cannot be opened from external side without the right key,it is often noticed that the internal knob has to be twisted manually by entering the hand through a nearby window. It may be more difficult. This problem has been overcome by the use of double cylinder deadbolts. As they poses a key hole and locking cylinder at both sides they can be opened from outside with the help of the right key.


A special type of deadbolt had been designed by Samuel Segar is the vertical deadbolt locking system. It resists the jimmying.


There are some other types of dead bolt locks also. These include single cylinder with removable thumb turn, classroom function, exit only and push button deadbolts.


The safety level should be measured using the double cylinder deadbolts. The key should be kept near the lock at floor level for escaping from any fire accidents.