To install a lock for a sliding patio door, close the door flush with its frame, place the lock in the appropriate position on the door, and drill the required number of holes in the door. Then, screw the lock in position using the holes, and install the bolts and the cover plate.
Closing the door flush with the frame is required to ensure that the lock fits properly after installation. If the door does not shut flush with its frame, clean the door's base using soap and a brush.
When positioning the lock on the door, place it near the door's edge and adjacent to the frame. If the lock works by stopping the door latch from shifting backward, ensure that the lock is positioned near the latch. Keep the latch and the door frame engaged.
While keeping the lock in position with one hand, drill several holes through the metal that is joined to the handle with the other hand. Avoid drilling through the glass or the door fabric. Insert screws into the holes to secure the lock in position. Next, attach the lock bolts on the frame so that they face and line up with the lock.
Finally, screw the cover plate on the door and above the lock, and join it to the bolts by moving the piece around.