Gross floor area in real estate is the total floor area inside the building envelope, including the external walls, and excluding the roof.
Definitions of GFA, including which areas are to be counted towards it and which areas are not, vary around the world. Adding to this confusion is the practice among some developers to use gross leasable area and GFA interchangeably, or to use GFA as GLA, even though GLA usually excludes corridors and other public areas inside the development, while both figures include areas occupied by structure, like walls and columns.
This video is targeted to blind users.
Article text available under CC-BY-SA
Creative Commons image source in video