Home › Glossary › Below Grade

Below Grade

Below grade describes space in a building whose floor sits below the level of the finished ground outside. Basements are the most common below-grade space.

A level is below grade even when only part of it is underground. Walkout basements, which open to the yard on one side, and garden-level units are still below grade under ANSI Z765, however much daylight they get.

Below-grade space is excluded from gross living area even when it is fully finished. Finished below-grade area is reported on its own line instead. See below-grade finished area in appraisals.