As you will have noticed, it is possible to define a minimum floor area for each individual space in BriefBuilder. This is usually done in terms of usable floor area (UFA): the amount of space that should be directly available for user activities, excluding ‘non-usable’ areas such as the space required for partitions or columns.
It is likely, however, that you also want to have an indication of the total size of the building in terms of gross floor area (GFA). That number does not only include the usable square meters, but also the square meters that are needed for technical installations, plant rooms, walls, columns and so on. This is quite a crucial number because it is often used for cost calculations.
To calculate the gross floor area of building or project, you can use the GFA/UFA ratio, which is a multiplier that is being used to go from usable floor area to gross floor area. This ratio can, for example, be 1.4 or 1.7, dependent on what type of building it concerns.
In BriefBuilder, the GFA/UFA ratio is available as a standard property of the object Building. You find that property on the detail view of a building object, but you can also find it in the area report that is available in the main menu under the header Overviews.
The area report is easiest to work with because that is where the total gross floor area is shown (in the last column in italics). The area report can be found in the main navigation menu, under overviews.


