The correct approach is not that one document generally overrides the other, but that each has its own regulatory scope. The founding deed records ownership relations: which units belong to the building, the size of each ownership share, what counts as separate and what as common property.
The bylaws in turn set the internal rules of operation: the competences of the bodies, the order of bearing common costs, the detailed rules for using separate property.
In practice this means that if a dispute concerns the size of an ownership share or the legal classification of a room, the founding deed governs. If the dispute concerns the allocation key of common costs, the competence of a committee or a procedural rule, the bylaws prevail.
The 2026 uniformity decision of the Curia confirmed exactly this principle: there is no general ranking between the two documents, in each case one must examine which regulatory scope the question belongs to.
A complicating factor is that the two documents sometimes conflict because one was amended and the other was not. In such cases it is worth reviewing and aligning both at once, not just fixing the disputed point.
If you are unsure which document governs a given question in your building, Merbo's legal partners are happy to help clarify the situation before a dispute escalates.
It is worth checking once a year, together with the annual report, whether the content of the two documents is in harmony. This regular review is far cheaper and less tense than clarifying contradictions in a live dispute.