HOME SECURITY—DEADBOLT LOCKS

by Frank Fourchalk

Deadbolt locks have been mentioned before in this series of articles; what are they? A deadbolt is a lock with a bolt that extends from the lock and enters into the doorjamb. The bolt enters a plate called the strike plate located on the doorframe. There are two types of deadbolt locks; a single cylinder deadbolt which has a thumb turn on the inside and is keyed on the outside, and a double cylinder deadbolt which is keyed on both inside and outside.

A single cylinder deadbolt should be installed on all solid or reinforced doors where access to locks and knobs cannot be gained by breaking adjacent glass. Double cylinder deadbolts should be installed on all doors where access to knobs and locks can be gained by breaking adjacent glass.

Extreme caution should be taken when installing a double cylinder deadbolt on a door used as a fire emergency exit. If this is the case the key should be left inside the cylinder whenever the home is occupied. The use of this type of lock in a private residence is not prohibited by specific legislation; however, the National Building Code of Canada prohibits the use of these locks on any public building.

It is very important to check and make sure that your existing deadbolts are functioning properly. I am always amazed when doing a home security check at the number of deadbolts incorrectly installed by the resident or the builder.

Check and ensure that the bolt on the deadbolt lock is at least one inch in length. It is now in the building code to install a minimum one inch bolt on all new homes. This bolt must be fully extended in order to function properly. If you find that the bolt is hitting against wood behind the strike plate, make sure that you remove it to allow the bolt to fully extend and thus function effectively. The doorjamb should have at least two three-inch screws in the strike plate. These screws will penetrate to the wall stud reinforcing the frame side of the door. This reinforcement helps to prevent the doorframe from splitting if a forced entry is attempted.

When purchasing a deadbolt don't be fooled by the price. Cheaper is not better. You can purchase a deadbolt inexpensively, but be careful of what you a re getting. Take the deadbolt out of the package and feel its weight. You can get an idea of the quality and strength by the weight. Some of the things to look for are a solid brass body, a free-spin collar, pick-resistant cylinders, saw-resistant bolts and steel shrouds that cover the bolt extension.

When evaluating the security of your home make sure you have deadbolts on all exterior doors, including those leading fro the garage and basement areas as well.