Agreeing a construction cost cap in the architect's contract

An agreed construction cost cap is part of the service the architect owes. According to the judgment of the BGH (Bundesgerichtshof, the Federal Court of Justice) of 13 February 2003 (VII ZR 395/01), the design is defective "if the architect does not comply with a construction cost cap agreed as a quality of the work" (unofficial translation). The cap is therefore not a wish of the client's but a standard against which the architect's work is measured.

A binding effect can arise even without a precise figure. In 2013 the BGH ruled that the client's Kostenvorstellungen (cost expectations) are "relevant even if they do not contain a precise upper limit for the building sum", and that as a rule they become part of the contract if the architect does not object to them (VII ZR 230/11, reported from the court's press release). An expressly agreed cap, however, is clearer, easier to prove and leaves less room for interpretation.

These are trends in published case law. Each decision concerns an individual case, and other courts may assess contractual arrangements differently. What follows for the client is a working rule, not a guarantee: the more precise the contract, the less depends on the court.

There is a tolerance only if the contract provides for one. Under VII ZR 395/01, a tolerance range comes into consideration "only if there are indications in the contract that the agreed building sum is not meant to be a strict limit". A client who wants a strict cap therefore words it expressly as such and avoids phrases such as "about", "approximately" or "probably".

A client who wants room for manoeuvre settles it in the contract. A target figure with an agreed range is a legitimate choice, for instance where the brief is not yet fixed. In that case the range belongs in the contract as an amount or a procedure, rather than being left to interpretation.

This article gives no figures for tolerances where the contract is silent. Case law on the point is not consistent; the article on cost risks, contingencies and tolerances sets out the different approaches.

The burden of proof is the reason to agree the cap in writing. According to the BGH judgment of 6 October 2016 (VII ZR 185/13, published in the IWW Quellenmaterial), a client who relies on a cap bears the burden of pleading and proving that it was agreed. Conversely, if the architect claims that the cap was later raised by mutual agreement, the architect has to prove that increase.

Two duties follow from this for the client. The original cap must be apparent from the contract or from a letter clearly linked to it. And every later adjustment must be documented just as clearly, so that a note in the minutes or an email cannot be read as a tacit increase.

Claim	Burden of proof under VII ZR 185/13	What the client keeps to hand
A cap was agreed	client	contract, annex, accompanying letter
The cap was later raised	architect	the client's own record of every change to the brief with a cost effect

The same decision shows what is at stake. If the agreed cap is not met, the client can claim damages (section 634 no. 4 and section 280(1) BGB, the Bürgerliches Gesetzbuch or German Civil Code), and under the principle of good faith (section 242 BGB) the fee can only be calculated on the basis of the cap. The details of these legal consequences are covered in the article When the architect exceeds the cost limit: the client's rights.

A cap is only as robust as its scope is unambiguous. The following five items turn a figure into an agreement that can be checked.

Item	Content	Why it is needed
Amount	a figure, not a range	a range is an indication of a tolerance
Scope	the DIN 276 cost groups covered	otherwise it is disputed whether external works, fittings or ancillary costs count
Tax	gross or net	otherwise an apparent overrun arises equal to the VAT
Base date	the price level the amount refers to	otherwise a price increase cannot be separated from a design deviation
Binding force	strict or with an agreed range	otherwise interpretation decides

The base date protects both sides. Without a price level, every overrun becomes a dispute about whether it is due to general price trends or to the design; the architect will claim the one, the client the other. With a fixed price level, the two can be separated arithmetically. How the budget is then adjusted to later price levels belongs to budget management, not to the cap itself.

A clause might read, for example: "The costs of cost groups 300 and 400 under DIN 276 shall not exceed the amount of [amount] euros net, price level [month and year]. The parties agree this amount as a strict cap and as a quality of the design services." This is an example of the structure, not a checked contract template; the actual wording should be left to a legal adviser.

The cap belongs in the contract before design begins. If it is agreed only after the Kostenschätzung (cost estimate), it follows the design instead of the other way round.

Where no objectives are yet fixed, the BGB provides a moment of its own. If essential design and supervision objectives have not yet been agreed, the architect submits a planning basis with a Kosteneinschätzung (cost assessment) for the client's approval (section 650p(2) BGB). This approval is the natural moment to write down the cap, and the special right of termination in section 650r BGB gives the client a way out at that stage. How this phase runs is explained in the article The target-finding phase: planning basis, cost assessment and special termination.

The fee is a separate question. A fee agreement under section 7 HOAI (the fee regulations for architects and engineers) must be in text form; if there is none, the base fee rate applies to basic services. How a fee agreement has been structured since the 2021 reform is covered in the article on fee agreements since the 2021 reform. For the cap, it is enough to note that both agreements belong in the same set of contract documents.

A cap that is not carried along with the brief loses its force. If, during design, the client asks for additional floor area, a higher standard or a new use, the basis on which the cap was agreed changes. If this goes undocumented, the architect will argue in a dispute that the cap was tacitly raised, and the client loses the clarity gained through the agreement.

The BGB gives the client a right to order changes in the architect's contract too. Section 650q(1) BGB declares section 650b applicable by analogy; under subsection (2), the fee for ordered changes follows the fee calculation rules of the HOAI, where the services are covered by it. A change to the brief can therefore shift both the fee and the cap, and both should be decided in the same step.

A change procedure in the contract keeps the two together. It can provide for four steps:

1. The client describes the desired change in writing.
2. The architect puts a figure on its effect on costs and fees.
3. The client decides in text form whether to order the change with an adjusted cap, without adjustment by saving elsewhere, or not at all.
4. The new cap is recorded as a numbered version.

A budget stated in a competition brief can be an agreement on quality. In its judgment of 2 October 2025 (12 U 123/24, published on the portal gesetze-bayern.de), the OLG Bamberg (Higher Regional Court of Bamberg) held that the client's binding cost expectations count as an agreement on the quality of the work. In the case decided, a budget of around EUR 4.2 million had been set in the competition brief and could not be met with the brief's programme; the court found initial impossibility (section 275(1) BGB), rejected the fee claim (section 326(1) BGB) and ordered repayment of the instalment paid.

The decision is not final. Proceedings against it are pending before the BGH under case number VII ZR 166/25 (the OLG did not grant leave to appeal on points of law). It shows a trend on which clients who commission through competitions cannot rely as settled law. It does, however, confirm a precaution: a budget in a competition brief should be stated with the same scope, base date and tax indication as a cap in a contract, because it may well be read in the same way.

It does not replace budget management. It obliges the architect to design within the limit, but it says nothing about price trends after the base date, about contractors' variation claims or about risks that only appear during construction. The client carries these items in the total budget, not in the cap.

It has no effect on the contractors. The cap binds only the architect. What the contractors charge depends on their contracts; there, the contract type, the specification and the procedure for Nachträge (variations) protect the budget.

It demands discipline from the client. A client who keeps extending the brief without formally adjusting the cap weakens their own position more than any wording in the contract can strengthen it.