Gross and net floor area: what is the difference?

Gross and net floor area: when purchasing a property, you may encounter what appears to be conflicting information on the same subject, such as floor area.

The square metres referred to by the seller may not be the same as those referred to by the buyer, or even, in some cases, by the estate agent. Let us look at the definitions for greater clarity:

• Ground-floor footprint: the number of square metres built on one level
• Total built area: the total number of square metres built. This includes all floors, garages, attics and cellars.
• Gross habitable floor area: the total floor area in square metres of the habitable rooms, including partitions, external walls and half of party walls. Please note that the ceiling height must be at least 1.50 m for an area to be considered habitable.

We can therefore consider that the net floor area is the area that can physically be lived in, excluding walls and stairwells.

The Professional Institute of Real Estate Agents explains that, from now on, “in order to clarify the situation for consumers, FPS Economy requires that, if a property's floor area is mentioned in an advertisement, the source and/or calculation method used to determine this floor area must also be stated”. This regulation should simplify your search and prevent you from being misled when searching for a property.

You now know everything relating to gross and net floor area in the property sector.

And, since a reminder is always useful, here are the formulas for calculating areas:

Square = S x S
Rectangle = L x W
Triangle = (B x H)/2
Parallelogram = B x H