Additional Works Without Written Authorisation: When the Employer Refuses to Pay

Imagine: you entrust the renovation of your house in Villeneuve-lès-Avignon to a contractor, with a fixed-price quotation for €50,000. The works begin, but very soon the contractor tells you that the plumbing needs to be redone, an electrical socket added, a beam replaced… “Minor unforeseen items, nothing serious,” he says. You agree verbally. At the end of the project, the bill amounts to €65,000. The contractor demands payment of the additional €15,000. Must you pay?

This is precisely the question that the French Supreme Court (Cour de cassation) decided in a judgment of 30 October 1978, which remains relevant today. The judges recalled a simple but often overlooked principle: in a fixed-price contract (a firm and final price), any variation or additional work must be authorised by a written document signed by the employer. Without such written authorisation, the contractor cannot demand a single cent more.

This decision protects the owner against financial overruns, but it is also a sword of Damocles for the contractor who works without a safety net. So, how to avoid the trap? Analysis.

The facts: a story that happens every day

Mr Riboldi, owner of a business in Uzès, entrusts renovation works to a contractor. The contract is a fixed-price contract: a global and definitive price for a precise list of services. But during the works, the contractor carries out additional works (plumbing, electrical, masonry) which Mr Riboldi allegedly verbally accepted. At the end, the contractor presents an invoice including these extras, which the owner refuses to pay.

The contractor sues Mr Riboldi. The Court of Appeal rules in his favour: it considers that, since the fixed-price contract was poorly drafted and it is impossible to distinguish precisely what was planned from what was added, the owner must pay the entirety of the works, including the supplements. Mr Riboldi appeals to the French Supreme Court.

The French Supreme Court quashes the Court of Appeal's judgment. It criticises the lower court for not having checked whether the employer had given a written mandate to authorise the additional works, as required by Article 1793 of the French Civil Code. This article requires that any modification of a fixed-price contract be recorded in writing. Without such written authorisation, the professional cannot claim anything.

The reasoning of the court — analysed

The French Supreme Court relies on Article 1793 of the French Civil Code, which provides that “the architect, contractor or other workers who undertake the construction of a building according to a plan agreed and settled with the owner of the land cannot demand any increase in price, nor any payment for works or supplies, under any pretext whatsoever, unless there has been a change or increase in the plan and such changes or increases have been authorised in writing by the owner.” In other words, the fixed price is a lock: to open it, you need a paper key, signed by the client's hand.

In this case, the Court of Appeal had circumvented the obstacle by declaring that it was impossible to precisely define the works due under the fixed-price contract. But the French Supreme Court replies: “You find that the parties intended to place themselves under the rule of Article 1793, so you must examine whether the owner gave a written mandate.” No written mandate, no payment, full stop.

This reasoning is a strict application of the principle prohibiting oral evidence for additional works. It is a rule of public policy, intended to protect the employer against surprise demands. The contractor must therefore imperatively obtain a written document before any modification. Failing that, he runs the risk of working for free.

This case law is constant and has not changed since 1978. It is regularly recalled by the courts, particularly in disputes concerning renovation of individual houses or condominiums.

What this means for you — practically

For the landlord owner: if you entrust works to a contractor under a fixed-price contract, you are protected. Any supplement not in writing is at the professional's expense. Example: in Uzès, an owner has a roof redone for a fixed price of €20,000. The contractor verbally tells him that the rafters need to be replaced for an additional €5,000. The owner refuses to sign a variation order. The works are done anyway. The owner can legally refuse to pay the €5,000, because no written document obliges him to do so.

For the tenant: if you have fitting-out works carried out in your home under a fixed-price contract, you are also concerned. Do not rely on a verbal agreement. Demand a written variation order before any modification. Otherwise, you could find yourself having to pay sums you had not planned, or conversely, being unable to refuse payment for works you had verbally requested.

For the professional: this decision is a warning. Never start additional work without a written document signed by the client. Even if the client says “go ahead, we'll sort it out later”, you put your remuneration at risk. In the event of a dispute, you will have to prove the existence of a written mandate, failing which your claim will be dismissed.

A quantified example: a contractor in Villeneuve-lès-Avignon carries out €8,000 of additional works on a €40,000 project, without a variation order. The client refuses to pay. The contractor loses his case and must also pay the legal costs. Moral: a written document is worth more than a long speech.

Four tips to avoid this type of dispute

• For any owner: never sign a fixed-price quotation without a precise description of the services. If the contractor proposes a supplement, demand a written variation order before the works begin. A simple email with read receipt may suffice, but a signed paper document is ideal.
• For any contractor: before carrying out any additional work, have a purchase order or variation order signed by your client. If the client refuses, refrain. You may lose a sale, but you will avoid a non-payment.
• For both parties: keep all written documents: quotations, invoices, emails, text messages. If a dispute arises, these are your only evidence. The case law requires a written document, but an electronic document may be accepted if it is reliable (e.g., electronic signature).
• In case of doubt: consult a lawyer specialising in property law before signing a variation order or refusing payment. A 30-minute consultation can save you thousands of euros.

Further analysis: related case law and developments

In the same year, the French Supreme Court issued a similar judgment (Civ. 3e, 30 Oct. 1978, No. 76-15.081) in which it also required a written document for additional works, even if the initial contract was imprecise. More recently, the French Supreme Court recalled this principle in a judgment of 12 January 2017 (No. 15-27.067): the absence of a written document prevents any claim, unless the employer has expressly acknowledged the debt in writing after the works.

The trend is therefore constant and severe for professionals. The judges consider that consumer protection prevails over apparent fairness. Thus, even if the works were useful and carried out with care, without a written document, the professional cannot claim a supplement.

For the future, it is possible that case law may evolve towards greater tolerance in cases of urgency or indispensable works (for example, a water leak requiring immediate intervention). But for now, the rule is clear: no written document, no payment.

Summary and next steps

FAQ:

• Q: Can a fixed-price quotation be modified orally? A: No, any modification must be authorised in writing (Article 1793 of the French Civil Code).
• Q: What if the contractor has already carried out additional works without my written consent? A: You can refuse to pay. But if you gave verbal consent, you risk being ordered to pay if the contractor proves your agreement (e.g., by witnesses). It is always better to demand a written document.
• Q: Is a text message or email sufficient as a written document? A: Yes, provided it comes from the employer and is clear about the nature and price of the works. A simple “OK” can be contested. Prefer a signed document.
• Q: What are the time limits for taking legal action? A: The limitation period is 5 years from the completion of the works (Article 2224 of the French Civil Code). For professionals, the period is 2 years (Article L. 218-2 of the French Consumer Code).
• Q: Can I claim damages if the contractor carried out works without my consent? A: Yes, you can claim damages for loss of enjoyment or deterioration of your property, but this is rarely granted. The main thing is not to pay for unauthorised works.

Are you in a similar situation? A first 30-minute consultation with Maître Zakine (€45) can save you months of proceedings — and often much more. Book an appointment →