Gross Building Area (GBA)
Calculated as area * levels.
Gross Building Area (GBA) is the total enclosed floor area of a building, measured from the outside face of its exterior walls, and it includes all levels, even unfinished or unheated ones like basements, garages, and mechanical areas.
Net Area (GFA)
Calculated as area * levels * efficiency
Gross Floor Area (GFA) is the total floor space within a building, including all levels, typically measured from the inside faces of the exterior walls. The definition may vary by municipality.
Saleable Area (NRA)
Calculated as area * levels * sellEfficiency
Saleable area is the total floor area that can be sold to a buyer, including the usable space inside the unit and sometimes the area of balconies and terraces.
Roof Area
Calculated as area - area of geometries with higher stack order in the same building.
The area of the exposed top face of a geometry.
Facade Area
Calculated as perimeter * floorToFloor * levels
Facade area is a measurement of the surface area of a building's exterior front. It is calculated by multiplying the length of the façade by its height, including elements like overhanging soffits, cornices, and protruding columns, as seen in a vertical plane
Facade is quite simple to compute for standalone building sections. However, this becomes more complicated when geometries touch.
Giraffe will attempt to figure out where the sides of geometries should count as interior or exterior walls. The facade settings in analytics and urban control the function.
Parti Wall Area
Calculated as length * floorToFloor * levels where two geometries touch
A party wall is a common dividing structure, such as a wall, located on the boundary line between two adjacent properties, owned by different parties, that serves as support for both structures.




