A jimmy plate is a strip of metal or other material placed in the upper door channel, above the sliding door. It is an effective way of preventing sliding doors from being lifted off their tracks, which is a common tactic used by burglars, according to the Jefferson City, Missouri, Police Department.
The plate essentially eliminates the space above the sliding door, locking the door onto its tracks by making it impossible to lift. Jimmy plates can be purchased at most hardware stores.
They can also be made at home. With the door open, simply glue or screw a strip of wood or metal along the upper track of the door.
Large pan-head screws can also be drilled into the upper channel. Whatever the material, make sure there's enough room for the door to slide shut but not enough space to lift the door from its tracks.
Safety bars will reinforce your sliding-door lock so that the door cannot be opened horizontally. Safety bars are a popular option because they are effective and cheap---all you need is a wood or steel cylinder of the right length.
Safety bars, sometimes also called "charlie bars," are placed in the bottom channel of the door, between the end of sliding glass door and the door brace. There is also another option for people concerned that burglars might find a way to dislodge the safety bar by methods such as drilling a small hole in the frame and pushing the bar out of the channel.
Many safety bars can be fastened to the door brace through a screw assembly that keeps the bar in place until it is lifted from the interior and folded vertically into the brace.
There are several kinds of interior locks designed to reinforce the locks on sliding doors. Most use a slide or deadbolt and are installed on the inside edge of the door track.
Many operate by pulling a pin or turning a lever. It is important, however, when considering auxiliary locks to keep in mind that you must be able to exit the house quickly in case of an emergency, such as a fire.
Conversely, if your home has a pool, consider a lock that is child-safe so that unattended children are not able to open the sliding door from the interior and access the pool. Locks that bolt the door to its frame will keep the door from being opened horizontally or lifted off its tracks.
The best auxiliary locks are made of solid metal and use at least a 1-inch deadbolt.