A sliding glass door operates much like a train. Rollers fastened to the underside of the movable panel are designed to glide along a track on top of the threshold.

Endura Flap Thermo Panel Pet Door for Sliding Glass Doors: This sliding glass doggy door only fits tracks that are at least 1 inch wide, but its adjustable height gives it some versatility.

Use a track lock One method of preventing the door panel from being opened on a sliding glass door is to block the tracks so the door can’t slide open. There are a variety of sliding door track ...

My sliding glass door, for example, straddles a single metal rib. If your door won’t move, it may have jumped off its rails.

Also, my sliding glass door does not have a very good lock, and I have used large sticks in the track to make it more secure.

We have a sliding glass door in our family room and are not sure what we should do on it. We had vertical blinds in our apartment and really didn’t care for them.