Construction Contract Law in Procurement 2026

Definition: Construction contract law comprises the totality of legal provisions governing the conclusion, performance and completion of construction contracts between contracting authorities and construction undertakings, and thus forms the private-law counterpart to the public-law rules of procurement.

Last updated: January 2026 · Legal status: BGB §§ 631–651, VOB/B, ABGB (Austria), ÖNORM B 2110, German Construction Contract Reform 2018

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What is construction contract law?

Construction contract law governs the legal relationship between the contracting authority and the contractor after the award and is therefore the private-law continuation of the public procurement procedure. While procurement law governs the path to selecting the contractor, construction contract law determines the rights and duties of the contracting parties when performing the contract.

Construction contract law is structured differently in Germany and Austria but follows the same fundamental principles: contract for work and labour, defects liability, adjustment of remuneration on performance changes, and termination.

Construction contract law in Germany

BGB construction contract (since 2018)

With the Act to Reform the Law of Construction Contracts (in force since 1 January 2018), Germany introduced for the first time stand-alone provisions for the construction contract in the BGB (§§ 650a–650v BGB). The reform brought several substantial innovations:

• Right of order by the contracting authority: The contracting authority may unilaterally order changes to the design or to the agreed scope (§ 650b BGB). The contractor is entitled to an adjustment of remuneration.
• Status assessment: Either party may demand a joint status assessment of the work (§ 650g BGB).
• Consumer construction contract: Special protective rules for consumers as building owners (§§ 650i–650n BGB).

VOB/B

VOB/B (Award and Contract Regulations for Construction Works, Part B) is the most widely used construction contract framework in Germany for public contracting authorities. It contains detailed rules on performance deadlines, billing, acceptance, defects liability and termination. Unlike the BGB construction contract, VOB/B provides a shorter limitation period for defect claims (four years instead of five years under the BGB) and specific rules for the settlement of unit-price contracts.

VOB/B applies only where it has been expressly incorporated into the contract. For public works contracts, this is required by VOB/A.

Construction contract law in Austria

ABGB and ÖNORM B 2110

In Austria, construction contract law is governed by the General Civil Code (ABGB) as part of the law on contracts for work and labour (§§ 1151–1164 ABGB). It is supplemented by ÖNORM B 2110 (General Contract Provisions for Construction Works), issued by Austrian Standards International, which is regularly incorporated into public works contracts.

ÖNORM B 2110 covers:

• Scope of services and deviations in quantities
• Price adjustment for additional and reduced quantities
• Performance deadlines and extensions of construction time
• Defects liability and warranty
• Invoicing and payment deadlines

Interfaces with procurement law

Procurement law and construction contract law form a coherent system: the procurement documents, especially the specification and the contract conditions, become part of the construction contract. Material changes to the contract after award are subject to the procurement-law restrictions on contract modifications (Art. 72 Directive 2014/24/EU).

FAQ

Which rules apply to public construction contracts in Germany? In Germany, public construction contracts are governed by the BGB (law of contracts for work and labour, §§ 631 et seq.) and – where incorporated – VOB/B. VOB/A obliges contracting authorities to incorporate VOB/B into their contracts.

Can a contracting authority unilaterally modify the construction contract after conclusion? Unilateral modifications are admissible only within narrow limits. In Germany, § 650b BGB grants the contracting authority a right of order, which however triggers adjustment-of-remuneration claims for the contractor. Under procurement law, material contract modifications must be treated as a new award.

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Last updated: January 2026 All information without warranty. For legally binding advice, please consult a law firm specialising in procurement law.