Modern trends have been towards 36 inches or 900 mm, based on the assumption that its purpose is to protect the wall from chair backs. The term ‘chair rail’ is also used for this reason. Dado rails are also sometimes applied to a wall without the full dado treatment.
In this regard, what is the proper height for chair rail molding?
Correct Height for Chair Rail Molding. Most experts place chair rails at one-third the distance of the ceiling height. For a standard 8-foot ceiling, they should be installed about 32 inches from the floor. Hull cautions that most people install chair rails too high on their walls.