Install strong locks and bolts on all exterior doors, since doors are particularly vulnerable to burglars. Older, worn locks should be replaced with newer, higher-quality units. If you are an apartment dweller, it is imperative that you change the lock/cylinder since you have no idea who might have access to the key.
The front door needs a strong lock, particularly for periods when you are not at home and it will not be bolted from inside. Back and side doors need extra protection since they are often targeted because they cannot be seen from the street; an intruder may try to open them with force.
Install good-quality dead-bolt cylinder locks or mortise locks in all exterior doors. If purchas¬ing a dead-bolt cylinder lock, look for a bolt that extends at least 1 inch beyond the edge of the door when in the locked position. Make sure the lock has a case-hardened cylinder guard, steel inserts, a reinforced strike plate, and tie screws a minimum of 3 inches long that secure from the inside.
A lock whose operation requires a key from both the inside and outside (a double-cylinder lock) may be a good idea for side and back doors. Without a key, a thief will have difficulty removing bulky property from the rear of your home and will be forced to leave through a window or the front door. Double cylinder locks also prevent a burglar from breaking the glass window in a door and reaching in and unlocking the door. (Since double-cylinder locks can be operated only with a key, they can be hazardous when used in doors that are the only means of egress in the event of fire and may even be prohibited by some city and/or county ordinances.)
The standard “thumb-turn” locks found on most double-hung windows are a mild deterrent for the average burglar, who can open them easily through a broken pane of glass. Locks oper¬ated by a removable key are the most secure. Since leaving the key in the lock decreases security, it is important that every mem¬ber of the household know where window lock keys are kept and how to use them. The installation of locks and protec¬tive grilles should always be considered in tandem with your emergency exit plan.
Dual Screws, Sash Stops, and Pins
An inexpensive but effective way of safeguarding windows is to immobilize movement of the sashes with a dual screw, nail, or pin that passes through both meeting rails. A hole is drilled through the inner meeting rail into the outer one, and then a dual screw (with bolt), nail, or pin is inserted until it is flush with the window frame. A second set of holes to permit the window to be partially open allows for ventilation.