Thank you all for your input. Clearly not all square feet are equal and that there is a continuum of “finishedness.” It makes sense that agree with tax records. I may explore having taxable square footage meet ANSI standards:
“Ceiling Height Requirements
To be included in finished square footage calculations, finished areas must have a ceiling height of at least 7 feet
(2.13 meters) except under beams, ducts, and other obstructions where the height may be 6 feet 4 inches (1.93
meters); under stairs where there is no specified height requirement; or where the ceiling is sloped. If a room’s
ceiling is sloped, at least one-half of the finished square footage in that room must have a vertical ceiling height of
at least 7 feet (2.13 meters); no portion of the finished area that has a height of less than 5 feet (1.52 meters) may
be included in finished square footage”
https://www.e-rallc.com/ANSIstandards
