It is a scenario many building owners fear: years after acceptance, the property shows serious defects. A crack in a load-bearing wall, a terrace beginning to sag, a roof losing its structural integrity. The contractor may have long since left the site, the architect may have closed the file. Yet Belgian law gives you a powerful weapon in such cases: ten-year liability under articles 1792 and 2270 of the old Civil Code.
This special liability is not a classic contractual guarantee. It is a matter of public policy, cannot be excluded or limited, and runs for ten years. But it is not unlimited either: only serious defects that affect or threaten to affect the stability of the building fall within its scope. And you must take legal action within the ten-year period — waiting is fatal.
What is ten-year liability?
Ten-year liability is a special statutory liability that rests on the contractor and the architect after the acceptance of the construction works. It is based on articles 1792 and 2270 of the old Belgian Civil Code. The liability applies to "serious defects that affect or endanger the solidity of the building or one of its main components, even due to the unsuitability of the ground".
Two actors are in the line of fire: the contractor who executes the works, and the architect who drew up the plans or supervised the works. In case of concurrent faults, both are jointly and severally liable — the building owner may hold each of them liable for the entire damage. This principle of in solidum liability is an important protection: you do not have to work out precisely which percentage of fault each one bore.
Which defects are covered?
Not every defect is a ten-year defect. Case law has clarified the threshold: it must concern defects that affect or endanger the stability or solidity of the building or a main component. Main components include load-bearing walls, foundations, roofs, and terraces where these are structural.
The Brussels Court of Appeal ruled on 13 January 2022 (JLMB 2022, no. 38, 1677) on a typical grey area: water infiltration. Although infiltration may in certain cases amount to construction defects threatening the stability of all or part of a building, the Court held that infiltration under kitchen walls does not automatically fall within ten-year liability. The defects observed did indeed cause damp at the base of the kitchen walls, but did not undermine the stability and solidity of the building — they merely made the property unsuitable for use. The building owner failed to demonstrate a genuine risk to stability, and could therefore not invoke ten-year liability.
Lighter defects that are not structural fall under the regime of minor hidden defects, with different time limits and conditions. For details on this distinction, see how long you have in the case of minor hidden defects after acceptance.
Time limit and starting point
The period is ten years and starts running from the acceptance of the works — in practice usually the provisional acceptance. It is a preclusive time limit (délai de forclusion), not a limitation period. That distinction is crucial: a preclusive time limit cannot be interrupted or suspended. You must take legal action within those ten years; a registered letter of default is not enough to safeguard the time limit.
In its judgment of 13 January 2022, the Brussels Court of Appeal clarified an important nuance regarding provisional acceptance with reservations. A contractual clause that gives provisional acceptance — even with reservations — the effect of recognition and starting point of ten-year liability, cannot have the consequence that defects expressly mentioned as reserved in the minutes are deemed covered. Those defects therefore remain within the scope of the architect's ten-year liability.
Public policy and its impact on exoneration clauses
Here lies the sharpest tooth of ten-year liability: it is a matter of public policy. This is not an academic classification but a direct sanction against all attempts to limit liability contractually.
The Court of Cassation confirmed this principle on 12 February 2021 (AR C.20.0066.N) and expressly repeated it on 10 February 2022 (AR C.19.0594.N): the special liability of architect and contractor for serious defects that affect or endanger the solidity of the building or one of its main components is a matter of public policy and can therefore not be excluded or limited contractually. A clause limiting this liability which, in case of concurrent faults by architect and contractor, seeks to limit their liability to their respective share in the damage, is consequently null and void — regardless of whether the works have been accepted.
The practical consequence: clauses in architect or construction contracts such as "each party is only liable for its own share" or "liability is limited to the amount of the fee" have no effect on ten-year liability. The court will set them aside. For other liability regimes (minor hidden defects, non-conformity without threat to stability) such clauses in principle remain valid, provided they respect the other rules of contract law — including the doctrine of unfair terms in B2B contracts.
What changes with Book 7 CC?
The draft Book 7 of the Civil Code of 16 April 2024 restates ten-year liability within a renewed framework. Article 7.4.49 CC speaks of "stability-threatening non-conformity defects" and provides that the contractor is liable for any non-conformity defect that arises no later than ten years from the acceptance of the immovable construction and that affects or threatens to affect the stability or solidity of the construction, even due to the unsuitability of the ground.
The Explanatory Memorandum makes explicit which defects are covered: "Must be considered as stability-threatening non-conformity defects, those non-conformity defects that affect the solidity or stability of the immovable construction or one of its main components (walls, roof, terraces, etc.) or at least endanger these in the longer term. An actual collapse or a risk of imminent collapse within the ten-year period is not required: a genuine risk of impairment of stability in the shorter or longer term is sufficient."
Three elements stand out. First, there is no notification period as for other non-conformity defects in article 7.4.18 CC. The Explanatory Memorandum motivates: "Given the severity of stability-threatening non-conformity defects, it may not be assumed that the client who fails to report the defect to the contractor within a reasonable time after discovery is deemed to have accepted the defect."
Second, it remains a preclusive time limit: the building owner loses their right if they fail to take legal action within the ten years.
Third, article 7.4.49 § 3 CC expressly codifies the public policy status: "Any clause seeking to exclude or limit the liability of the contractor for the non-conformity defects referred to in paragraph 1 is absolutely null and void." The case law of the Court of Cassation is thus confirmed in the legislative text itself.
The mandatory professional liability insurance
Since the Act of 31 May 2017, mandatory insurance for the ten-year civil liability of contractors, architects and other service providers in the construction sector applies. No one may practise as an architect without being insured, and the Act contains sanctions for non-compliance.
What if an insurer invokes the fact that the architect did not declare a specific project? The Mons Court of Appeal ruled in its judgment of 23 March 2023 (For.ass. 2023, no. 235, 124) that the failure to declare a project constitutes an exception or forfeiture that cannot be invoked against the injured party. The duty to declare governs the relationship between insurer and insured but does not delimit the object of the insurance. The public authorities and the building owner as injured parties should not suffer from administrative negligence by the architect.
The Brussels Court of Appeal reached the same conclusion on 25 January 2024 (JLMB 2024, no. 42, 1903). For the building owner, this is an important reassurance: even if the architect failed in their declaration duties, ten-year insurance cover in principle remains in place. For details of this issue, see what risks an architect without site supervision entails.
What to do in case of a serious defect after acceptance?
The ten-year period runs relentlessly. Any delay is a risk. A sensible approach:
First, a preservation expert investigation. Findings by a court-appointed expert or by an amicable expert on an adversarial basis form the evidentiary basis for your claim. A bailiff's report alone is rarely sufficient for technical issues (Brussels 4 January 2024, JLMB 2024, no. 27, 1204).
Next, a written notice of default to both contractor and architect, mentioning the identified defects and setting a deadline for proposals. Send registered mail, and keep proof of dispatch.
Finally, and critically: a writ of summons within the ten-year period. As set out above, a notice of default does not interrupt the preclusive time limit. If you wait until the last moment, a lost day may mean that your right lapses entirely. Reius Advocaten guides building owners through every stage of a ten-year liability claim, from the first findings to the proceedings on the merits. Contact us in good time at info@reius.be.
Want to understand your full position as a building owner? Read our guide on the rights and duties of the building owner.