Annulment of a sales contract due to an error on essential elements

Facts

Ms. Stalder purchased a plot of land in Samedan from Mr. Mathis in 1964 with the intention of building a vacation home. After the conclusion of the contract, it was established that the plot was located in an avalanche risk zone and that a building permit could not be issued. Ms. Stalder therefore requested the annulment of the contract due to an error on the essential elements of the contract.

Considerations

The Federal Tribunal granted Ms. Stalder's request. It considered that the error on the buildability of the plot was essential within the meaning of Art. 24 para. 1 no. 4 CO, as it constituted the basis of the contract for both parties. Although the prohibition to build was only pronounced after the conclusion of the contract, the risk of avalanche already existed beforehand…