Barn Door Height
The graphic below simulated a door over the opening.
Barn door height. In this example the total height is 83 when closed over the opening the door will cover all of the casing for a cohesive look. Barn door measuring guide for door openings with casing molding. Most barn door sizes fall anywhere between 36 wide on the shorter side by 96 tall on the longer side. Add 1 to 2 per door for overlap depending on privacy needs.
Measure from outside to outside of casing molding. 72 would probably be even better. For the door height we recommend measuring from the floor to the top of the casing. Measure across for the width and from the top of the casing molding to the floor for height.