Their exceptional status goes back to the time of France's first paid holidays in 1933, and distinguishes them from ordinary houses, road vehicles and certain types of light leisure accommodation dedicated to holidays.

AFNOR standard NF 956-410, which came into effect on 20 December 1999, gives mobile homes an official definition while clarifying their legal status, which had hitherto been uncertain.

At the same time, it ratifies the criteria previously provided in the 1933 circular.

The main points to remember are as follows:

• A mobile home shall be a "mobile leisure residence" for temporary and/or seasonal use. Under no circumstances whatsoever shall it be considered as a main residence.
• It shall only be used on special sites, such as campsites or fully-equipped residential leisure parks.
• On the campsite or residential leisure park, it shall be moved by ordinary traction.
• The mobile shall be supported on blocks set on the ground, and shall be connected to various networks for water supply and evacuation, as well as gas and power, in accordance with effective official regulations.
• The mobile home and its accessories shall occupy only 30% of the surface area of the space attributed to it.
  The maximum surface area of a mobile home is 40 square metres. Above this limit, the regulations for light leisure accommodation become applicable, requiring a building permit from the town hall (Mairie).
• Any annexes to a mobile home, such as awnings, terraces, store-rooms or garden sheds, for example, shall not under any circumstances whatsoever hinder directly or indirectly its mobility.
• A mobile home shall keep its means of mobility: wheels, connections to a tractor vehicle, tow-hook. It is the principle of mobility, rather than that of temporary immobility, which defines a mobile leisure residence and determines its legal status. The principle of mobility involves the definition of so-called "substantial" components of a mobile home, which automatically answer this criterion.
• called "substantial" components of a mobile home, which automatically answer this criterion.
• On the other hand, all the so-called "non-substantial" components of a mobile home – as defined by the Paris Court of Appeal in a decree of 6 July 2001– are those which have lost any possibility of mobility, such as:
  - an awning affixed to the ground in such a way that it cannot be moved,
  - the full range (variable) of equipment specific to the site accommodating the mobile residence. For example, any equipment for a permanent connection to the water-supply network is specific to the site rather than the mobile home.

Any components relating to the mobility of the mobile home are thus considered to be so-called "substantial" components which shall be provided by the seller.

When moving into a campsite or a residential leisure park: any accessories and annexes shall be included when calculating the occupation of 30% of the surface area. They shall fulfil precise standards: the terrace shall automatically be raised to a minimum height of 60 cm (2 ft) from the ground, and any rigid awning shall be removable.

Some site managers may forbid such accessories and annexes – provided that this is explicitly stated in the site regulations – while some départements (French administrative areas) may require an administrative authorisation.
If it exceeds the maximum surface area of 40 square metres, a mobile home is liable to be considered as light leisure accommodation, although the standard has nothing to say about this. In any event, in addition to the site occupation fee, the owner of the mobile home shall pay for supplies of water, gas and power, as well as fees for sewage and household waste disposal. However, all these sums may be included in a lump-sum contract.

It should be noted that only power supplies are considered as a service.

The site manager has no right to directly invoice electricity, which is the sole prerogative of EDF (the French power monopoly).
The price paid corresponds to a proportion of the overall power bill and the amortisation of the corresponding installations: transformer, cables and power points. If campsites or residential leisure parks are equipped with individual electricity meters, invoices shall be paid directly to EDF, of which the resident is a direct subscriber.

In terms of insurance, mobile homes are considered to be caravans. If an insurer offers a "residential" policy, furnishings and accessories are not covered.

As far as taxation is concerned, only a taxe de séjour (accommodation tax) is payable, and only in municipalities frequented by tourists which have introduced such a tax.

Mobility, space and comfort are the advantages of mobile homes; both today and in the future, their practicality and simplicity under any circumstances shall be recognised by naturists.