Estimate overrun

Estimate overrun

I signed a contract with a company to carry out work on my natural stone roof based on an estimate of CHF 1,864. What a surprise to receive an invoice for CHF 4135 once the work had been completed! I complained to the company concerned, who told me that the price quoted was an estimate and that the final price corresponded to the actual price, because the installation of some of the stones had taken longer than expected. Is this legal?

J. Valais

The law defines a contract of enterprise as one in which the contractor undertakes to carry out a work in return for a price that his client - called the master - undertakes to pay him. The contractor has an obligation of result and must deliver the work free of defects.

If the parties do not agree on a fixed price or a lump sum, the price of the work will be calculated according to the work carried out. The contractor's approximate estimate therefore plays an essential role in the client's decision to enter into the contract.

Moderate overruns of the estimate must be tolerated but, unless otherwise specified in the contract, it is generally accepted that the estimate should not exceed 10%, unless of course this is the result of the master's own behaviour, omissions or additional requests. In the event of excessive overruns, the law allows the client to withdraw from the contract or to request an appropriate reduction in the price of the work.

It should be noted that the contractor has a duty of loyalty to the owner, which gives rise to a duty to inform, which covers, among other things, excessive overruns of the estimate. Thus, the contractor must notify the client as soon as he realizes that the amount indicated in the estimate will be greatly exceeded, failing which the client will be entitled to compensation for damages resulting from late notification that would have prevented him from withdrawing from the contract or from taking steps to try to remedy the problem.

In order to calculate the fair reduction to be made to the price of the work, legal doctrine and case law consider that the amount exceeding the initial estimate (to which the permitted margin and overruns attributable to the contractor must be added) must be shared fairly between the parties, taking into account the circumstances and the good faith of each party. This often means "splitting the difference", which in your case would theoretically reduce your final bill to CHF 3093.