The international building code has established doorknob height between 34 and 48 inches above a finished floor.
Standard bore height for door handle.
The bore hole is the large diameter hole where the door knob is mounted.
Through the edge of the door there is a 1 cross bore that extends from the edge of the door through the bore hole.
Their position should be between 900mm 1050mm 35 5 41 5 inches above the floor.
Generally the knobs should be of a free moving slide action.
The requirements of bs 8300 provide for a door knob to be between 800mm 1050mm 31 5 41 5 inches from a finished floor.
Most interior doors are prepped with a single boor hole.
Standard height the standard height for doorknobs on a typical 80 inch tall household door is 36 inches.
Why this is standard is not certain.
All handles pulls latches locks and other operable parts of the door should measure between 34 inches and 48 inches above the floor.
The height of the door handle is not so much the problem as the door handle itself.
The standard sized bore hole is 2 1 8 in diameter.
Installers typically drill the hole centered 36 inches above the floor if not specifically instructed to do so differently.
Exceptions to the rule include doors that provide egress into swimming pools or other water features.
The most likely explanation is that as we began to mass produce doors the centre of most middle rails in the typical drop panelled door was 36 inches from the bottom of the door.
Fortunately the standards for ada door handle height are not much different than traditional recommendations.