You’ve just discovered a zoning violation on your property. Or you’re in the process of selling, and the notarized deed reveals that work was done without a permit. Or you’ve received a letter from the authorities.
In any case, the same question arises: how much will the regularization cost?
The answer depends on your region (Wallonia, Brussels, Flanders), the nature of the violation, the municipality in question, and the approach taken: rectification of the violation, restoration, amnesty, or sale as-is. Administrative fees, surveying costs, additional technical studies, and follow-up fees: each item varies.
What you'll find here: a clear breakdown of each cost, the factors that drive the price up or down, the timelines to expect, and two examples with specific figures—ranging from a simple addition to an illegally subdivided building. No sugarcoating.
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✓ 50% des dossiers < 4 858€ (stats 2024)
Before taking any action, the property must be accurately measured and documented. This forms the basis of the regularization file: without reliable data, no application for a building permit will be approved.
At Ubex, this step involves point cloud surveying, a technology that captures three-dimensional space with centimeter-level precision. This is not the same as a hand-drawn sketch or a rough plan produced by a traditional surveyor: the documents produced are legally binding and leave no room for dispute when your municipality’s urban planning department reviews the application.
The cost of this phase varies depending on the building's size, its accessibility, the complexity of its layout, and the number of rooms to be documented.
Any application for a retroactive permit is subject to an administrative fee payable to the local government. These amounts are not fixed; they depend on the type of permit requested, the applicable retroactive procedure (with or without a public hearing, with or without a review by the consultation committee), and the municipality in question.
In the Brussels Region, an urban planning violation in Brussels that is handled in Anderlecht, Auderghem, Forest, Ganshoren, or Molenbeek will not follow exactly the same administrative process as a case investigated in Namur or Liège in the Walloon Region. Each urban planning department has its own procedures, timelines, and priorities regarding land use planning and zoning.
Sometimes, the real cost isn’t in the application fee, but in the time it takes to navigate local zoning regulations. That’s precisely where local expertise makes the difference between a project that moves forward and one that stalls.
Depending on the nature of the violation and the agency's requirements, certain cases may require specific studies. The most common ones are:
These studies are not systematic, but they are not merely anecdotal either. Ignoring them at the outset of the case risks causing delays during the proceedings and prolonging the time it takes to obtain the regularization permit
Four factors determine the complexity—and therefore the cost—of a case:
The nature of the violation. A change of use (converting a commercial ground floor into residential space, dividing a single-family home into apartments) is structurally more difficult to regularize than an undeclared addition or extension. The specific actions and work involved, their age, and their initial legal status determine the entire analysis.
The region and the municipality. The Walloon Region, the Brussels Region, and Flanders do not have the same rules, procedures, or deadlines. Even within the same region, each municipality has its own particular sensitivities. Some grant permits easily; others apply particularly strict standards, especially regarding land-use planning issues.
The chosen approach. Regularization is not always the only option. Depending on the case, the analysis may point toward an amnesty, restoration to compliance, or a sale of the property "as is" with the buyer informed of the legal status. The path chosen determines the scope of the work and, therefore, the final amount excluding tax.
The property's history. A case where documents exist, are accessible, and are consistent moves forward much more quickly than one where everything has to be pieced together. The absence of plans, title deeds, or previous building permits invariably complicates the task.
This is the second most frequently asked question, right after the cost. And the answer varies just as much.
In the Walloon Region, the permit approval process follows the deadlines set by the CoDT. For a standard planning permit application, the processing time is generally 60 to 75 days, which may be extended if a public hearing or a consultation committee is required. In practice, actual processing times often exceed these legal minimums, depending on the workload of the relevant planning department.
In the Brussels region, processing times are similar in theory, but the urban planning regularization process in Brussels can take longer in certain municipalities with high real estate demand or in cases involving complex changes in land use. An application for regularization that requires an environmental permit or affects public space may involve additional steps.
For example, a straightforward case that does not require a public hearing can be resolved in 3 to 6 months. A complex case involving a consultation committee, additional studies, and potential appeals can take 12 to 24 months.
What speeds up the process: a complete application package from the very first submission, a thorough preliminary review, and familiarity with local administrative practices.
The procedure for applying for an urban planning regularization permit follows specific steps, regardless of the region in question.
Step 1: Assess the situation. Before taking any action, you must identify the exact nature of the zoning violation, evaluate the available options (regularization, restoration, amnesty), and assess feasibility based on the zoning regulations in effect in the municipality. This preliminary assessment determines the course of action moving forward.
Step 2: Prepare the application package. The application package must include scanned copies of the property’s current plans, documents certifying the land use, any required supplementary technical studies (energy performance, structural stability, acoustics), and the administrative forms specific to each region. An incomplete application upon submission will automatically result in requests for additional information and further delays.
Step 3: Submit the application and follow the review process. The application is submitted to the municipality’s urban planning department. The review process may involve a public hearing, a hearing before the consultation committee, or requests for opinions from specialized agencies. Actively monitoring the application during this phase is crucial to avoiding delays.
Ubex every step of the process: from the feasibility study through to obtaining the regularization permit. With an hourly rate, you only pay for the work actually performed, and the project can be terminated at any time.
The CoDT in the Walloon Region and the CoBAT in the Brussels Region provide for a system of fines proportional to the severity of the violation. Fines can reach €25,000 for the most serious violations, with aggravating factors including repeat offenses, construction in a protected area, refusal to cooperate, and the danger posed by the structure.
These fines do not replace the process of rectifying urban planning violations; they are in addition to it. The penalty and the cost of bringing the property into compliance are cumulative.
Any unresolved violation must be disclosed in the sales contract. This is not optional. Concealing a violation makes the seller liable for ten years following the transaction.
The practical implications for the selling price: a discount of 10% to 30% on the appraised value, refusal by banks to provide mortgage financing, and systematic downward pressure from buyers during negotiations.
In the event of legal proceedings, the court may order the structure to be brought into compliance: partial or total demolition of the annex or structure in question, at the owner’s expense. Work to bring the structure into compliance, which would have cost a few thousand euros to regularize, may require €15,000 to €30,000 in restoration work. This does not include daily penalties in the event of refusal to comply.
A house with a 30-square-meter addition built without a building permit. It is possible to regularize the property’s planning status. The cost of the process is offset by the difference in value between a property that is compliant and one that is not, and especially by the elimination of the risk associated with resale. Without regularization, the discount on the sale price consistently exceeds the cost of the process.
A single-family home divided into four units without a building permit. Estimated value as a single-family home in its current condition: approximately €580,000 (after deducting estimated renovation costs of €70,000). With legalization and sale as four separate units: up to €880,000.
The difference is approximately €300,000. The fees for a case of this complexity range from €20,000 to €30,000, excluding VAT.
It's not magic; it's well-planned urban design.
Our 2024 statistics cover only our fees (excluding administrative costs and technical studies). Based on this: the amounts range from €591 to €8,082 (excluding VAT), with 50% of cases handled for less than €4,858 (excluding VAT).
These figures reflect the diversity of situations, not a standard rate. A straightforward case in a cooperative municipality proceeds differently from a case in a protected area involving a public hearing or a consultation committee.
What remains the same: With an hourly rate, the project can be paused at any time. You only pay for the work that is actually completed.
The question is: "How much will it cost me if I don't regularize my status?"
And in this case, the numbers rarely support doing nothing.
Contact Ubex
AddressesUbex
Avenue Louise 523 B1050 Brussels
Chaussée de Marche 482 B5101 Namur
Rue Bois Gotha 98 B4000 Liège
Rue de Bart Haut 6 B6790 Aubange
Beekstraat 6 B9030 Gent
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