The federal document is not a standard specification
This is the least understood point, and it is stated unambiguously by the body that publishes it. The federal system is a classification and not a specification.
The property manager of the federal state distributes a technical reference document, widely present in Belgian professional tools and available in French and Dutch. But it is neither a standard specification nor a reference specification.
Three consequences follow.
Citation is excluded. Unlike the CCTB, it cannot be referred to by simple citation. The texts must be transcribed into the specification for which they are intended.
Its maintenance is partial. Texts relating to structure, foundations, loadbearing masonry, concrete, steel and timber, are kept current. The other chapters have not been dealt with since 2008.
It is obtained on request. It is not freely downloadable like the regional frameworks.
Anyone transcribing a non-structural chapter of this document today is therefore transcribing a text frozen for more than fifteen years. That is an elementary check, and rarely made.
Enumerative and faceted systems
This technical distinction is the key to the subject, and it explains a difficulty many practitioners observe without being able to name it. Classifying a work and describing it are two different operations.
An enumerative system organises elements in a single hierarchy, where each item occupies a determined position. The CCTB and the Flemish technical framework belong to that family: their classification is a table of contents, and the index of an element is its position in that table.
A faceted system describes the same object along several independent axes, for instance function, form and material. An object then receives several codes that combine, rather than a single position.
The official Belgian system derived from the international building classification standard, published by the federal body and freely usable, belongs to that second family. It serves to order information rather than to prescribe works.
Why this governs the link with the model
This is the practical consequence, and it explains why attaching quantities remains laborious in Belgium. No automatic bridge exists between classification and bill.
Belgian specification frameworks are enumerative. The systems used to classify model objects are predominantly faceted.
Moving between them is therefore not a simple translation of codes. An object described by several facets must be attached to a single position in a hierarchy, and that operation has no general automatic solution: it depends on the project, the level of detail adopted and the conventions agreed.
Hence the recurring observation: quantities come out of the model, but their attachment to items is redone on every project.
This subject is developed in the article on measurement, BIM and coding. The link between model and bill is covered there.
| System | Nature | What it does |
|---|---|---|
| Walloon framework | Standard specification | Describes the works and prescribes |
| Flemish framework | Standard specification | Describes the works, text integrated |
| Federal system | Classification | Orders information, does not prescribe |
| Private coding | Project structure | Stabilises the breakdown from project to project |
Private coding systems
Alongside public systems, coding schemes are distributed by software vendors and maintained by practices. Their contractual status depends on the contract that invokes them.
They answer a real need, that of having a stable structure from project to project, but they add a layer to the exchange problem. They add in return one more framework to manage.
Three situations are commonly encountered. They differ by the framework the particular specification invokes.
A practice uses its own internal coding and converts it to the required framework when issuing documents.
A tool imposes its structure and offers correspondences to public frameworks.
A project defines its own coding, often within a digital collaboration protocol, which is recommended practice in a BIM environment but presupposes that all parties comply.
What this means for a professional
Four rules.
Never present the federal document as the federal counterpart of the CCTB. It has neither its status nor its method of use.
Check the date of chapters transcribed from that document, maintenance being limited to structure.
Identify the nature of the system before attempting a correspondence. Enumerative to enumerative is laborious. Faceted to enumerative is design work, not conversion.
Fix the coding at the start of the project, not when producing the bill. A late choice forces rebuilding what already exists.
This article reflects the position of professional frameworks at the date of checking and serves as orientation. It does not constitute legal advice and does not replace consulting the official sources.