The CCTB explained: tomes, editions, obligations

The CCTB is the text that almost every building specification in Wallonia cites on its first page. It is rarely explained from end to end, though: where it comes from, how it is numbered, what a new edition changes, and what a project author actually does with it when writing a cahier spécial des charges. This guide takes each of those points in turn, with dates and sources, for the architects and engineering practices that work with it every day or are meeting it for the first time.

What the CCTB is

The CCTB, Cahier des charges type – Bâtiments, is the reference specification for the construction and renovation of buildings in Wallonia. It is published by the Service public de Wallonie (SPW). It is not the specification of a project: it is a library of clauses, administrative and technical, from which the project author draws to compose the special specification of a given contract.

That library holds about 9,500 elements. Each element describes a work item or a product: what it includes, the materials allowed and their requirements, how it is carried out, how it is measured and paid. The requirements point to the standards in force, first of all the NBN standards and the Eurocodes, rather than rewriting them.

The CCTB exists in French. Its purpose, as the SPW puts it, is to give every party in the act of building a common language: the client, the project author, the contractor and the subcontractors read the same clauses, numbered the same way, from one contract to the next. A quantity surveyor who priced article 21.11.1A in one project finds the same article, under the same number, in the next one.

The full name of the current generation is "Cahier des charges Type-Bâtiments 2022", usually shortened to CCTB 2022. The successive editions of that generation carry a version number: 01.09, 01.10, 01.11, up to 01.13 today.

Who publishes and maintains it

The publisher of the CCTB is the Service public de Wallonie, through its Département de la Gestion immobilière. The text is made available free of charge on Wallonia's buildings portal, for online consultation and for download, edition by edition. Earlier editions remain available in an archive section, because a running contract keeps referring to the edition it cited when it was signed.

The CCTB grew out of the Walloon Region's wish to unify the specifications of its public authorities, each of which used to write its own. The first edition of the current generation, 01.01, dates from 10 February 2014. Since then the SPW has published a new edition roughly every year, after a review in which the professional federations of the sector take part.

Around the official text there is an ecosystem of support. The Union Wallonne des Architectes (UWA) acts as CCTB facilitator for its members: answers to usage questions, model documents, training. Continuing-education bodies, among them IFAPME and the SPW itself, offer introductory and advanced sessions on the CCTB and on VitruV. A private site, cctb.be, publishes explanations and tools outside the official channel and points to the SPW portal for the reference text.

How the CCTB is structured

The CCTB is organised in eleven volumes, called tomes, which roughly follow the chronology of a building site. Tome A gathers the administrative clauses; tomes 0 to 9 gather the technical clauses.

The numbering has seven levels, the tome included, with digits and letters. The cctb.be portal names them as follows: the tome (one digit or the letter A), the section (two digits), the title (two digits, a point, one digit), the subtitle (two digits, a point, two digits), the chapter (one more digit after a second point), the article (a letter) and the item, or poste (a point and two digits).

An example, taken from tome 6: 61 is a section; 61.7 a title; 61.71 a subtitle; 61.71.1 a chapter; 61.71.1A an article; 61.71.1A.01 an item. The article is the level the project author really specifies: it carries the text of the clause. The item is the line of the bill of quantities attached to that article, with its quantity, its unit and its measurement type.

In daily practice, people often say "lot" for the tome and "chapter" for the two-digit section. Everyone understands those words, but they are not the ones of the official structure. When a specification cites a number, the numbering is what counts, not the name given to the level.

Each article of the CCTB itself follows a regular composition. Its description says what the work includes and excludes. Its materials fix the products allowed and their characteristics, with the standards that apply. Its execution describes the installation. Its measurement specifies the unit and the mode of payment: lump-sum quantity, presumed quantity, global price, sum to justify or for the record. Some articles add references to annexed documents, inspections or tests.

The editions, from 01.01 to 01.13

The SPW publishes a dated edition, identified by a version number. The table below lists the thirteen editions of the current generation, as the SPW portal archives them.

Edition 01.13, published on 17 March 2026, is the edition in force at the time this guide is written. A new edition updates the administrative and technical clauses: articles are added, others are merged, renumbered or withdrawn; normative references are updated when an NBN standard changes; official texts are corrected. The SPW accompanies each edition with release notes that list those changes. Those notes are the first thing to read at every transition: they say which numbers have disappeared, which have moved and which texts now read differently, and they spare an article-by-article comparison of the whole specification.

For the project author, the edition matters at two moments. When a new specification starts, the edition in force is the base: a contract launched today cites CCTB 01.13. During the contract, on the other hand, the edition does not change: the special specification has fixed the edition it follows, and that edition governs until acceptance, even if the SPW has published a newer one in the meantime. That is what the portal's archive is for.

The move from one edition to the next is where practices' own libraries wear out. A specification template built on edition 01.11 cites numbers that, in edition 01.13, may have been renumbered or withdrawn, and texts the SPW has changed. Bringing that template up to date article by article calls for a comparison between the two editions; that is the work some tools automate, in whole or in part.

Where the CCTB is mandatory, and where it is a reference

The obligation to use the CCTB rests on three decisions, which the Service public de Wallonie recalls in its frequently asked questions.

In 2013 the Walloon Government approved the use by public authorities of a single reference specification, the cahier des charges type bâtiments, for all construction and renovation works on housing and buildings carried out by or on behalf of Wallonia and of the Société wallonne du logement, and for works those institutions subsidise at 50 % or more.

In 2014 the Government of the Fédération Wallonie-Bruxelles approved the same principle for all construction and renovation works on buildings carried out by or on behalf of the Federation, and for works its ministry subsidises at 50 % or more. The Union Wallonne des Architectes dates the CCTB's entry into application to 1 July 2014.

Since 1 January 2020, the public-service housing companies must use the CCTB alone for the technical part of their specifications.

Outside those three cases, the obligation exists only when the contract creates it: a contracting authority, a municipality, an intermunicipal body, a hospital or a school, can impose the CCTB in its own contract documents, and many do, sometimes also requiring a specific exchange format for the files. A practice bidding for those contracts therefore reads the client's special specification before choosing its reference text.

For private works the CCTB is not imposed by default. Two reservations remain: a private project subsidised at 50 % or more by Wallonia, the Société wallonne du logement or the Fédération Wallonie-Bruxelles falls back under the obligation, and the client, the project author or the subsidising authority can impose the CCTB in the contract. Outside those cases it has nonetheless become the de facto reference for French-speaking project authors, because a specification built on the CCTB is understood by every contractor, because its measurement clauses avoid settlement disputes, and because it is free. Many practices therefore use it for all their projects, public and private, adjusting the level of detail.

In practice, a firm therefore checks three things before choosing its reference: who the client is, whether a subsidy of at least 50 % is involved, and what the contract documents prescribe. If the CCTB appears in any of the three, the choice is made; otherwise it remains a free, but sensible, choice.

One clarification the SPW itself makes: the obligation bears on the text, not on a piece of software. VitruV, the drafting application the SPW publishes, is not mandatory; what counts is that the special specification follows the CCTB in the edition it cites.

The CCTB is a Walloon text. In Flanders, social housing follows the VMSW's standard specification, and road and public-space works in Wallonia follow QUALIROUTES, the CCTB's road counterpart, also published by the SPW. A project that combines a building and its surroundings can therefore cite two reference texts.

From the CCTB to the special specification

The CCTB is the library; the special specification, the cahier spécial des charges or CSC, is the project's document, the one tenderers price and the contractor carries out. Going from one to the other always follows the same logic.

The project author starts by selecting the articles that describe the works of the project: a few hundred articles out of the CCTB's thousands. The text of the CCTB is not copied into the specification. The special specification states that "the CCTB in its version 01.XX forms an integral part of the contract documents" and cites each article by its index and its title. The reference text then applies without being reproduced, which keeps the document short and avoids copying errors.

The CCTB then leaves choices open, wherever a general clause cannot decide in the project's place. Those passages are flagged in the reference text, in colour, and the project author must complete them: a strength class, a finish, a thickness, a brand or a type followed by the words "or equivalent". A choice left open is a gap in the specification: the contractor cannot price it.

The project author also adds provisions of their own where the CCTB does not cover a particular work, or where the project imposes a stricter requirement. Those project-specific articles take the same composition as the CCTB's articles, description, materials, execution, measurement, so the reader does not switch grammar halfway through the document.

Then comes the bill of quantities. Each selected article receives one or more items, with a quantity, a unit and a measurement type consistent with the article's measurement clause. The estimated bill of quantities accompanies the special specification in the tender documents; the summary bill, priced by the tenderers, becomes their offer. The coherence between the clause, the item and the offer hangs on a single thread: the article number, identical in the three documents.

Before the contract is published, the special specification is re-read with a few questions in mind. Has every open choice been settled? Is every brand named followed by "or equivalent"? Does every cited number exist in the stated edition? Does every item of the bill point to an article present in the document? These are mechanical questions; they are also the ones that, when forgotten, cost the most once the contract is out.

The tools that work with the CCTB

The CCTB can be worked in a word processor and a spreadsheet; that is still how many specifications are produced. Several programs are, however, built around it.

VitruV is the application published by the Service public de Wallonie itself. Free, it installs on a workstation and lets you compose a special specification by selecting and adapting CCTB articles, then produce the descriptive document and the bill of quantities as DOCX and XLSX. The SPW states that its use is not mandatory: the project author may use another drafting application, provided the text of the CCTB is followed. VitruV exports its projects in the .cdcx format.

ArchiMind is an online workspace for the specification and the bill of quantities, published by Phi Consulting SRL in Charleroi. It imports VitruV's .cdcx export and a project's IFC model, proposes clauses from the practice's template while identifying the target article, derives the bill of quantities from the model, migrates a project from one CCTB edition to the next with a preview, and checks the document before issue. It also supports the VMSW's standard specification and QUALIROUTES.

ArchManagement is practice-management software for architects and engineers, built around the CCTB specification and the bill of quantities, which adds site follow-up and fee invoicing. Metrarch, by Softarch, is bill-of-quantities and specification software for architects and engineering practices, whose version 5 integrates CCTB 2022.

The choice of a tool depends on the size of the practice, on the share of public contracts in its work and on what it expects from the link between text and quantities. What they all share: the reference text remains the SPW's, and it is the text, not the tool, that governs.

CCTB, VMSW, QUALIROUTES: three Belgian reference texts

An architect active in several regions or on several kinds of works meets three reference texts.

The CCTB covers buildings in Wallonia and, by extension, in the French-speaking part of the country. The standard specification of the VMSW, the Vlaamse Maatschappij voor Sociaal Wonen, now part of Wonen in Vlaanderen, covers social housing in Flanders; it is still known by the VMSW name and serves as a reference well beyond social housing. QUALIROUTES, published by the SPW, covers roads, sewers, paving and external works in Wallonia.

The three texts share a logic, a reference cited by its edition and numbered articles, but not their numbering nor their measurement clauses. A project that cites two reference texts must say so clearly, tome by tome, so the contractor knows which text applies to which item.

What to remember

The CCTB is a library, not a form: the value of a special specification lies in the selection, in the settled choices and in the bill of quantities that accompanies it. Its edition is fixed when the contract is signed and does not move afterwards. Its numbering, over seven levels, is the thread that ties the clause, the item and the offer together. And the tools, whether published by the SPW or by private publishers, serve the same text.

Sources and references

• SPW — CCTB edition and downloads
• SPW — CCTB archive
• Wallonia — About the CCTB
• SPW — CCTB and VitruV FAQ