When Silence Becomes Liability
A site supervisor discovers during a walkthrough that the waterproofing specified by the architect is not suitable for the existing soil conditions. He says nothing, builds according to the plan, and collects payment. Two years later, he is left alone with water damage in the basement. A notice of concern (Bedenkenanzeige) exists for exactly this situation: it shifts the risk of a defect caused by someone else back to the client, provided the contractor warned in time, concretely, and in a way that can be proven. A contractor who stays silent, or who only mentions something verbally on site, is usually still liable, even when the underlying error was not theirs.
What the notice of concern covers
Section 4(3) VOB/B (Vergabe- und Vertragsordnung für Bauleistungen, Part B, Germany's standard terms for construction contracts) requires the contractor to raise concerns about:
- the method of execution specified by the client,
- the quality of materials or components supplied or specified by the client,
- work by other contractors that serves as a precondition for the contractor's own work, to the extent it endangers proper execution.
This affects nearly every trade: the shell construction contractor who has to build on a defective foundation, the electrician who has to work with materials provided by the client, the tile layer who is asked to work on screed that is still too damp. The notice is not a formality. It is a genuine obligation, and failing to meet it has consequences.
Form and timing: without delay and in writing
Under Section 4(3) VOB/B, the notice of concern must be in writing and submitted without delay, ideally before the affected work begins. Without delay means as soon as the contractor recognizes, or should recognize, the concern, without culpable hesitation. A contractor who only raises the issue after installation has usually acted too late, even if the concern itself is technically correct. A verbal notice on site is not sufficient, even if it is noted in the site diary; it can supplement the written notice to the client, but it cannot replace it. A structured format for this kind of written notice is available in Structify's templates.
Who should receive the notice
In practice, a notice of concern is often sent only to the site supervisor or the architect, because there is no direct contact with the client. Legally, that is often not enough: the correct recipient is usually the client itself, not only the site supervision team, unless that team has been expressly authorized to receive such declarations. In practice, it is advisable to address the notice to the client and inform the site supervisor or specialist planner at the same time. Anyone unsure whether the site supervision team is authorized to receive such notices should clarify this in advance or, to be safe, address both.
Proving delivery, not just claiming it
In a dispute, the contractor must prove that the notice actually reached the client in time. Common methods include:
- registered mail with return receipt,
- delivery by courier with a written confirmation of receipt,
- fax with a transmission report and a note of the content,
- handover against signature on site, with date and name.
Email is risky unless there is a read receipt or some other confirmation of receipt, because the client can dispute having received it. An entry in the site diary does not replace the notice to the client, but it serves as additional evidence of timing and content.
The legal consequence: relief from defect liability under Section 13(3) VOB/B
The real value of the notice of concern shows up once a defect occurs. Under Section 13(3) VOB/B, the contractor is relieved of defect liability if the defect results from a method of execution prescribed by the client, from materials or components supplied or specified by the client, or from preliminary work by another contractor, provided the contractor properly raised concerns about it and the client nevertheless insisted on the execution. Properly means in time, in writing, and specific enough in content that the client could grasp the scope of the risk. If the notice is missing or too general, liability for the defect stays with the contractor, even if the underlying error did not originate with them.
What belongs in the notice
A general statement such as "we have concerns about the execution" is usually not enough. The notice should include:
- a specific reference to the affected work item or position,
- a concrete description of the technical concern, including why it is in question,
- the possible consequences, including what defect or risk is at stake,
- a request for a decision or instruction from the client,
- where time is short, a deadline for a response.
No explicit rule under a BGB construction contract, but a comparable duty
Under a construction contract governed only by the BGB (Bürgerliches Gesetzbuch, Germany's civil code) without a VOB/B agreement, there is no provision that literally matches Section 4(3) VOB/B. According to case law, however, a comparable duty to review and point out concerns usually applies: a contractor who, as a professional, recognizes or should recognize that preliminary work, a specified material, or an instruction given by the client is unsuitable, usually has to point this out before carrying out the work. The exact requirements and consequences depend on the individual case. This is not legal advice but an orientation that should be examined further with legal counsel if a dispute arises.
How site supervision should respond
For site supervision, a notice of concern is not an annoyance but a basis for a decision. It makes sense to:
- review the concern promptly on technical merits, rather than letting it sit,
- involve a specialist planner or structural engineer if needed,
- document the decision in writing: either a revised instruction or an explicit instruction to proceed as planned despite the concern,
- inform the contractor of the decision before the affected work begins or continues,
- document the matter in the project file with date, content, and decision.
An instruction to proceed despite a concern is permitted, but it shifts the risk for that particular defect to the client, provided the notice itself was proper.
Checklist
- Raise concerns in writing as soon as they are recognized, not after installation
- Address the notice to the client, not only to site supervision
- Name the affected work item or position specifically
- Describe the technical concern and its possible consequences concretely
- Ask explicitly for a decision or instruction
- Document delivery to the client in a way that can be proven, for example registered mail, courier, or signature
- If instructed to proceed despite the concern, get that instruction confirmed in writing
- Keep the site diary and meeting minutes as additional, not substitute, evidence
- Under BGB contracts without VOB/B, take the comparable duty to point out concerns just as seriously
- Seek legal advice early if a dispute is likely
Conclusion
A notice of concern is not bureaucratic overhead. It is the difference between "I warned" and "I am liable." Three things matter: the right timing, the right recipient, and proof of delivery. Anyone who gets this right protects themselves from defect liability that was never really their responsibility.
In Structify, a notice of concern can be captured directly during a site walkthrough: speech is automatically turned into a record, and the related defect can be documented with its location on the plan, a photo, and a deadline. External parties such as the client can be invited through a guest link, so the notice reaches the right place in a traceable way. If you would like to see how this looks on your project, book a short online demo.