What is considered finished square footage?

Finished square footage is space built for year-round living: finished walls, floor, and ceiling, heated, and connected to the rest of the house through other finished space. Under ANSI Z765 it also needs a ceiling at least 7 feet high, or 6 feet 4 inches under beams and ducts.

Finished area and living area are not quite the same thing. A finished basement is finished square footage, but because it is below grade it is reported apart from gross living area. Only above-grade finished space counts as gross living area.

Heat alone does not make a space finished. A heated garage, an unheated sunroom with drywall, and an attic room reached by a pull-down ladder each fail at least one test, so none of them count.