A fence does not constitute proof of the boundary of a property, even though the line of the fence may have been agreed between the owners, a French court has ruled.

In a case recently heard in the French Supreme Court, the Cour de Cassation, the owner of a property near the city of Toulouse contested that a boundary line mutually agreed between neighbouring owners constituted the definitive boundary between the two properties.

The boundary line had been agreed in 1978 between the father of the current owner of the property when the neighbours had jointly undertaken the construction of a boundary fence.

The court heard that determination of the boundary line had been undertaken by the plaintiff's father, using as the baseline a plan that had been prepared to obtain planning consent for their neighbour's house.

However, unknown to her father their neighbour concealed the fact that the actual construction was larger by 1.5 metres than that shown on the planning consent.

As a result, the fence later constructed was not shared, but on the property belonging to the plaintiff.

The court noted that the boundaries as recorded on the French land registry, the cadastre, merely gave an approximate indication of the boundaries.

Nevertheless, the Court of Appeal took the view that despite the error that had been made the boundary had been mutually agreed between the parties and was therefore definitive.

This interpretation was not accepted by the Cour de Cassation, who considered that mutual consent was not irrevocable unless the boundary line had been determined by a land survey undertaken by a qualified geometre, in a process called 'bornage'.

Accordingly, the judges ruled that the boundary line should be changed and that the plaintiff be awarded damages.