A typical placement is one or two feet above the knob but it can be lower.
How to install a door slide bolt.
How much strength do you need the bolt to have.
Level up the door bolt and then mark drill and screw the top screw hole nearest the door.
To install your security slide bolt lock you must first determine whether your door is inside sliding or outside sliding.
The closer it is to the center of the door the more.
Close the door up until the keep touches the door frame.
Glue this to the door where you want the bolt lining up the front edge of the plywood with the edge of the door.
Install and secure all 3 screws.
Then screw the bolt onto the plywood.
Install the barrel bolt at a height that is easily reachable.
Be sure that the hole is large enough to eliminate any binding of the slide bolt.
An outside sliding is a door in which the moving door is on the outside of the house whereas an inside sliding places the moving door on the inside of the house and the fixed one on the outside.
If you need a stronger latch it will require a lot more work.
Mark fixings for door keep.
Extend the bolt out slightly and push the bolt keep over it.