Three separate codes
| Region | Applicable code | Consent |
|---|---|---|
| Wallonia | Code du Développement Territorial (CoDT) | planning permit |
| Flanders | Vlaamse Codex Ruimtelijke Ordening (VCRO) | omgevingsvergunning |
| Brussels-Capital | Brussels Code of Spatial Planning (CoBAT) | planning permit |
These are not three variants of one model. They are three autonomous texts, each with its own list of exempt works, its own procedures and its own periods.
The practical consequence is direct. Internal alteration of a house may be entirely exempt on one side of the language border and require a permit on the other. No Belgian rule can be stated without naming the region.
Flanders adds a structural feature: since 2017 the planning permit and the environmental permit have been merged into a single consent, the omgevingsvergunning. That merger simplifies the file but does not necessarily shorten the process.
Consent periods vary threefold
This is the most measurable difference, and it bears directly on carrying cost. Each extra month of processing is paid in finance charges.
| Region | Consent period |
|---|---|
| Flanders | 60 days simplified, 105 days ordinary procedure |
| Wallonia | 75 to 115 days depending on procedure |
| Brussels-Capital | 160 days from a complete file |
These periods run from the date a file is declared complete, which is not the date of submission. In practice several further months elapse between submission and consent.
For a developer or private client, the difference between 60 and 160 days translates into finance cost, prolonged professional fees, and exposure to price movement between estimate and tender.
In Brussels the ordinary procedure additionally involves a thirty-day public enquiry and a consultation committee, which explains part of the gap. Both steps come on top of the processing period itself.
Energy requirements are not aligned
Each region has transposed the European framework in its own way, with its own thresholds, vocabulary and timetable. An identical project is therefore not costed the same way from one region to another.
Even the name of the certification differs: PEB in Wallonia and Brussels, EPB in Flanders. Required levels for new build, calculation methods and renovation deadlines for existing stock also diverge.
For new build, Wallonia has applied the Q-ZEN standard since 1 January 2021, setting high requirements for insulation and airtightness. A further requirement applies from 1 January 2026: a minimum share of renewable energy in annual primary energy consumption. The other regions apply their own levels, expressed in their own indicators.
Requirements and their cost effect are covered in the article on energy requirements by region. The thresholds are given there region by region.
Support schemes follow three logics
This is the most fast-moving area and the one demanding most caution. The support schemes are recast at a rapid pace.
Wallonia operates a transitional regime and is moving to a new system based on loans and on improvement in energy label.
Flanders narrowed its principal grant to lower-income households in March 2026, widening its loan scheme in compensation.
Brussels offers a reduced-rate loan accessible under conditions to tenants as well as owners, which is rare in Belgium.
A support scheme quoted without its region and its date is unusable. These schemes change several times within a legislature, and an amount read six months ago may no longer exist.
Where the cost difference actually sits
Beyond procedure, four items carry the real difference. None of them belongs to the construction price proper.
| Item | Nature of the difference |
|---|---|
| Mandatory studies | nature and number vary by region and type of works |
| Carrying cost | consent period, varying threefold |
| Energy requirements | levels, indicators and timetables all differ |
| Available support | schemes, ceilings and conditions without equivalence |
Municipal taxes on permits sit alongside these, belonging to a third level of decision and varying between municipalities within a single region. They are therefore checked with the municipality concerned rather than the region.
The detail is covered in the article on permit costs by region. The amounts are given there by region and by type of file.
What this means for an estimate
Three consequences for anyone costing a project in Belgium. They concern the region, the municipality and the timetable.
A benchmark per m² does not transfer between regions without checking. Two identical projects in Wallonia and Flanders share neither energy requirements, nor ancillary costs, nor carrying cost.
The region is established before the benchmark, not after. It determines which items belong within the scope.
The municipal level sits above the regional one. Municipal regulations, taxes and practice vary within each region, and the municipal planning department remains the reference contact.
The articles in this branch
The article on Wallonia covers the Q-ZEN standard, CoDT periods and the support regime under reform. The Walloon grant scheme is set out there in its current state.
The article on Flanders covers the omgevingsvergunning, renovation obligations and the narrowed grant scheme. The Flemish renovation obligation is detailed there.
The article on Brussels covers the CoBAT, the regional planning regulation and the constraints of dense urban fabric. The dense fabric imposes site constraints of its own there.
This article reflects the position of the rules at the date of checking and serves professional orientation. It does not constitute legal advice and does not replace assessment of the individual case.