Design over budget: what the client can do

The sources examined show no tolerance threshold. Nor do they show any Court of Cassation ruling dealing specifically with a design whose cost exceeds the client's spending limit. No text states that a gap of a given percentage is acceptable and that the designer becomes liable beyond it. Anyone quoting a percentage "from case law" without naming the decision should be treated with caution.

Nor, among the rules checked, is there any professional conduct duty to design within budget. The private client's footing is therefore contractual: the limite di spesa (spending limit) written into the appointment and the information the designer must give in writing. Decree-Law 1/2012 (art. 9(4)) requires the professional to inform the client of the complexity of the assignment, "all useful information about the foreseeable costs" from appointment to completion, and the fee by way of an outline quote, "compulsorily, in written or digital form" (unofficial translation).

There is, however, a general principle on the result owed by the designer. Every line of reasoning starts there, with the caution required by a principle that arose from a different case.

According to the line taken in a Court of Cassation decision, the designer is bound to deliver a design that can actually be used. According to Cass. civ. no. 8058/2023, reported by BibLus on 13 April 2023 and in the avvocato.it case summaries, the designer is a "debtor of a result", meaning a "design that can actually be used". If the works cannot be built because the design is wrong or inadequate, there is a breach, and the client may refuse payment by raising the defence of non-performance under art. 1460 of the Civil Code.

The case concerned planning compliance, not a budget. The design could not be built for reasons of planning compliance, not because it cost too much. Transposing the decision to a cost overrun is an interpretation, not a rule: a design that complies with the rules but costs twice the spending limit may be just as unusable for the client, but no decision examined says so.

The cautious reading is as follows. When the spending limit is written into the appointment, cost becomes one of the features of the expected result, like floor area or intended use; a design that exceeds it by a wide margin comes close to a design that does not match what was asked for. When the limit is not written, the client has to prove that the budget was part of the agreement, and the argument becomes fragile.

The strength of the client's position is read in the appointment, even before the estimate. The table summarises the typical situations; how to draft the clause is covered in Writing the budget into the designer's appointment.

A clause for revision at no extra fee is contractual, not statutory. No rule requires the designer to rework a design that exceeds the budget free of charge; if the appointment provides for it, the client has a clear tool, otherwise it has to negotiate.

A gap is not challenged as a block: it is broken down. There are three possible causes, and each leads to a different conclusion on responsibility.

• Prices. If the estimate applies more recent prices than the budget, part of the gap reflects the market, not a design error. It should be isolated by recalculating the estimate at the budget's price date, or by updating the budget to the estimate's date.
• Quantities. If quantities have grown compared with the previous stage for the same brief, the question is why: more accurate measurement, new technical choices, solutions more expensive than necessary. This is the cause most directly attributable to the design.
• The brief. If the client asked for more floor area, finishes or services, part of the gap is the client's own. Ignoring it makes the challenge hard to believe.

Documenting the gap requires a common basis. Comparing the designer's estimate with a bill drawn up on other quantities, or with a simple quote, proves nothing; the difference between an unpriced and a priced bill of quantities helps clarify what is being compared. When the amount justifies it, an independent cost check, prepared by a third-party professional on the same documents, gives the client a defensible reference.

The options run from the most cooperative to the most adversarial, and it pays to take them in order. Jumping straight to conflict stalls the project and rarely saves money.

1. Ask in writing for the design to be revised. A letter or a PEC (certified email) that refers to the spending limit, states the measured gap and asks for a revision proposal by a deadline. This is the step that matters most, because it fixes the date from which the client flagged the problem. How to approach the revision is covered in The estimate exceeds the budget: what to do before awarding the works.

2. Document the gap. Break the gap down into prices, quantities and brief and, if necessary, commission an independent estimate. The document serves both the technical discussion and, if there is a dispute, as evidence.

3. Serve formal notice. If the revision does not arrive or does not reduce the gap, a formal notice sets out the breach the client believes exists and the deadline for remedying it. The content of the notice should be prepared with a lawyer.

4. Consider withholding payment. The line cited admits the defence of non-performance under art. 1460 of the Civil Code for a design that cannot be built. Applying it to a design that is merely too expensive is a choice to weigh carefully: if the court does not share that reading, the client is in breach in turn.

5. Take legal action, as a last resort. Litigation comes after the project has stopped and the budget has already been compromised by delays. Its cost, in time and in expense, is worth estimating as one option among others.

Four behaviours take the force out of a challenge, often without the client noticing. The first is an oral budget, or one mentioned only vaguely, which leaves room to argue that the spending limit was an indication and not a condition.

The second is changes to the brief requested without a record: an extra room, a better finish, a different system asked for in a meeting and not recorded. Each one shifts part of the gap onto the client.

The third is approving stages without reservation. Accepting the design for a stage and paying its fee with no comment on the estimate makes it harder, at the next stage, to argue that the problem already existed. The fourth is leaving the estimate and the budget undated, which makes it impossible to separate the effect of prices from that of the design.

Cutting the designer's fee does not bring the design back within budget. The fee weighs little compared with the works, and withholding it as a bargaining lever without a contractual basis exposes the client to a claim. Larger clients face an additional limit: Law no. 49 of 21 April 2023 on equo compenso (fair remuneration) applies to dealings with banks and insurers, with businesses that in the previous year had more than 50 workers or annual revenue above 10 million euros, and with the public administration. The respective responsibilities of designer, works director and project manager are covered in Designer, works director, project manager: who answers for cost.

In the public sector, the limit sits in the design brief and the check is mandatory. The documento di indirizzo alla progettazione (design brief) states "the economic limits to be respected and any indication of the financial cover for the works" (Annex I.7 to Legislative Decree 36/2023, art. 3(g)), and design verification establishes whether the design complies with the brief (Legislative Decree 36/2023, art. 42(1)). A design that exceeds the economic limits must therefore be revised to come back within them, or the stazione appaltante (contracting authority) must knowingly change the limits and the financial cover. The process is described in Design verification and validation: what they check on cost.