Significant changes: definition
It must be considered (1) that there is a change in the risk for the insurer as soon as a conversion requires the vehicle to be re-approved by the DREAL, i. e. when it is a “significant” change.
Article R.106 of the Highway Code states that “any single vehicle or vehicle component that has undergone significant alterations must be subject to a new type-approval”.
However, according to the indications in Circular No. 84-84 of 24 December 1984 adopted for the application of the Order of 5 November 1984 on the registration of vehicles, only certain minor bodywork modifications (under the conditions provided for in Article 12 (&12-1) of the Order of 19 July 1954) of the unladen weight, the P.T.A.C. or the PTAC/PTRA couple (vehicles approved under several weights) do not require an individual type approval.
As a result, all changes affecting the following characteristics of the vehicle description notice are considered as significant changes:
assembly of the chassis,
number of axles,
wheelbase, track and overhang front and rear,
axle weights and loads,
engine (for replacements other than identical replacements),
transmission of movement,
In short, practically all the amendments affecting the technical information on the vehicle registration document require the vehicle to be presented to DREAL for approval on its own.
One conclusion must be made in all its rigour: the possibilities of modification are extremely limited for those who wish to avoid a transition to DREAL because any initiative outside this framework would expose them to total or partial cancellation of the effects of the vehicle’s insurance policy.
The potential consequences of a technical modification of your car do not only concern its insurance but also the regularity of your situation with regard to the rules of registration and circulation of vehicles which are laid down in the Highway Code.
In particular, driving with a transformed vehicle without new approval by DREAL may constitute several different offences (in particular art. R. 238 and R. 241 of the Highway Code) punishable by fines of up to 5,000 francs.
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