Hi Suecee:
6'8" or 80 inches to center of shower arm off finished floor is the industry standard. The shower arm is bent which lowers the shower head so most people can reach to adjust.
I also apply coomon sense when installing shower arm height..if short people, I reduce rough in to 78". If tall people I might increase to 82". BUT I would not reduce to say 72" because people are only 5 feet tall...that would be a problem for next people moving in. SO, standard practice is as I just presented. Standard rough in standard...80" off finish floor...
Hope that helped. If it did please
RATE THIS ANSWER. Thank you...Mark
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