Belgian construction law has traditionally developed through a combination of case law, sector-specific customs and extensive contractual arrangements, rather than through a comprehensive statutory framework. While this approach has allowed for a high degree of contractual flexibility, it has also resulted in an increased importance of negotiation and contractual arrangements, particularly in complex projects involving multiple actors and interfaces. Against this background, Book 7 aims to articulate general principles applicable to construction agreements, situating them within a broader legal framework while introducing specific rules tailored to immovable works.
In January 2026, we hosted a webinar addressing the key innovations proposed under Book 7 with respect to sale, lease and construction agreements relating to immovable property. This article reflects the part of that presentation devoted to construction agreements. This article outlines the key features of the draft legislation dated 20 February 2025, with particular attention to (i) the qualification of construction agreements as a subcategory of service agreements, (ii) the codification of the double acceptance mechanism in the Civil Code, (iii) the conformity defects, and (iv) the proposed regimes governing limitation periods, including the observations raised by the Council of State.
1. Construction agreements as a subcategory of service agreements
Book 7 introduces a general regime for service agreements, defined as contracts under which a service provider, acting without subordination, undertakes to perform a material or intellectual service for a client.
Construction agreements are expressly recognised as a specific subcategory of service agreements. In addition to the general regime on service agreements, Book 7 provides distinct provisions for services relating to immovable works, including in particular:
- the construction, transformation, or demolition of immovable property or a part thereof; and
- design or technical services, including architectural and engineering services.
By embedding construction agreements within the broader framework of service agreements, Book 7 promotes conceptual coherence within the Civil Code, while at the same time preserving rules that reflect the technical complexity and economic realities inherent in construction projects.
2. Codification of the double acceptance mechanism
3. Conformity defects
4. Limitation periods: clarification tempered by the Council of State’s observations
Book 7 introduces differentiated limitation regimes depending on the nature of the defects. While this structure is intended to enhance legal certainty, it has given rise to concerns, notably in the Council of State’s advice of 28 April 2025.
5. Conclusion: codification as a tool for smoother negotiations
The draft provisions of Book 7 reflect a clear intent to structure Belgian construction law by codifying established principles within a coherent statutory framework. By placing construction agreements under the general regime of service agreements and formalising mechanisms such as double acceptance and decennial liability, the legislator seeks to consolidate existing case law and market practice.
As highlighted by the Council of State, certain aspects of the draft raise practical and interpretative questions that may still evolve during the legislative process.
For practitioners, Book 7 brings greater clarity to the legal framework governing construction agreements, while largely preserving contractual freedom, as most of its provisions remain suppletive.
Careful contractual drafting will therefore continue to play a key role in structuring projects and allocating risk.
For further information or to discuss the impact of Book 7 on your future construction projects or transactions, do not hesitate to contact one of our lawyers below.
