The living area and the Carrez law area have a common point. They are both composed by the surface of the floors of the constructions. Only, it is necessary to deduct the spaces occupied by the partitions, the walls, the cages, the steps of the staircases with the doors and the windows. If this is the case, what is the difference between the total surface area and the Carrez law surface area?

Difference on the layout of the concerned spaces

The Carrez law considers the unfinished attic, with the storerooms, the shed and the veranda. However, it is necessary that the ceiling height of these rooms is equal or superior to 1,80 m. The surface area of these rooms is thus part of the Carrez law surface.
Like the Carrez law surface, the living area concerns only the fitted out spaces. It targets the surfaces that are automatically habitable. Thus, the habitable surface excludes immediately the surface of attics, verandas, sheds and storerooms.

Legal acts requiring their mention

Some legal acts require the mention of the Carrez law, but deny the mention of the habitable surface. It all depends on the type of property for sale or rent.
As a concrete example, the Carrez law is only useful in the sales documents of condominium lots. But still, it is necessary that the latter have an area of at least 8 m². The Carrez law surface must imperatively be in the preliminary contract as well as in the authentic act of sale. However, the Carrez law surface area does not apply to individual houses.
The living area is required in the lease contract in the case of rented accommodation. But the mention of the living area is required if and only if the rental property is a principal residence. In the case of a seasonal rental, it is not mandatory.

The accuracy of the measurements is required

The measurement of the living area and the Carrez law area does not require the intervention of a specialist. It is not mandatory, but it is more advantageous for the owner.
In case of error of measurement and that if the difference reaches the 5% compared to the real measurements, then, the owner risks big. This is because the buyer can claim a reduction in the sale price.
Then, false information in the lease contract can lead the tenant to ask for a rent reduction. The rate of reduction that he will ask for depends on the difference between the measurements given and the reality. Therefore, the intervention of a specialist is essential.
In short, it is necessary to know how to differentiate the living area from the Carrez law area. It is by knowing the difference that you can properly complete the legal acts related to the sale or rental.