You have just discovered that your extension, terrace, or facade opening, built without a permit, places you in violation of urban planning regulations. violation of urban planning regulations ? The question on your lips is: how much will it cost to regularize this?
Between €1,500 and €5,000 on average. But this amount hides a much more complex reality. Architect's fees account for up to 70% of the bill, administrative costsvary by a factor of two between Wallonia and Brussels, and some owners discover hidden costs too late: surveyor, energy performance studies, administrative finesof up to €25,000, etc.
Regularizing an infringement is not just a simple administrative procedure. It is an investment that protects your property, secures a future sale, and avoids penalties. In this guide, we break down each item of expenditure: from the architect's fees to municipal taxes, from technical reports to procedural deadlines. You will know exactly where every euro goes and how to optimize your budget to turn this legal obligation into a good investment.
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Understanding the cost of urban planning regularization means first identifying all the expense items that make up your final bill. Contrary to popular belief, the price is not limited to architect's fees alone. Here is a complete breakdown of the costs you should anticipate.
The architect's fee is the largest expense, generally representing between 60% and 70% of the total cost of your regularization. Depending on the complexity of your case and the scope of the assignment, you can expect to pay between €1,000 and €4,000 excluding VAT.
This range is explained by the diversity of services: drawing up compliant plans, drafting administrative documents, submitting the permit application, and following up on the file with the municipal or regional administration. A simple facade modification will require fewer hours of work than a complex extension involving plot division or the conversion of an unauthorized apartment.
UBEX a transparent and fair approach: instead of a flat fee that may not reflect your actual situation, we work on an hourly rate basis. Why? Because at the outset, before contacting the urban planning department, it is impossible to know precisely what steps need to be taken. This method ensures that you pay the fairest price , tailored to the specifics of your violation.
When we open your file, we charge €81 excluding VAT for opening costs to prepare the initial contact with the authorities and analyze your situation. Once the steps to be taken have been clearly identified, we will send you a detailed estimate of our services, which we will update as your project progresses. Our 2024 statistics show that a request to UBEX between €591 and €8,082, with 50% of casesresolved for less than €4,858: a controlled investment to secure your property.
To draw up plans that accurately reflect your building, a precise architectural survey is essential. This task allows each element of your building to be defined with precision: room dimensions, location of openings, ceiling height, and location on the plot.
UBEX the surveying of your buildings and, thanks to its network of trusted professionals, guarantees that the price of the survey is calculated as accurately as possible. This coordinated management saves you from having to search for a professional yourself and ensures you get the best price without any unnecessary intermediaries. Our established network allows us to negotiate favorable terms, which we pass on directly to your final bill, while maintaining impeccable service quality to ensure your file is compliant.
Each application for a regularization permit incurs administrative fees payable to the government. These amounts vary considerably depending on your region:
Depending on the nature of your violation and the requirements of the administration, you may sometimes need to plan for additional technical studies, which will increase your budget:
These professional services are not systematic but should be anticipated from the outset of your process to avoid unpleasant financial surprises.
In addition to the main items, there may be some additional expenses:
| Expense item | Price range | Mandatory? |
|---|---|---|
| Architect's fees | $1,000 - $4,000 excluding tax | Yes |
| Surveyor's report (house) | €2,000 - €3,500 excluding VAT | Generally yes |
| Administrative costs Wallonia | 375 € | Yes |
| Administrative costs Brussels | Variable (€300–500) | Yes |
| Energy Performance Certificate | $300 - $600 | Depending on the case |
| Stability study | $500 - $1,500 | Depending on the case |
| Acoustic report | $400 - $800 | Depending on the case |
| Urban planning taxes | Variable | According to municipality |
| Miscellaneous expenses (documents, travel) | $100–$300 | Yes |
| AVERAGE TOTAL | $1,500 - $5,000 | - |
| Complex cases | Up to $8,000 | - |
Delaying or ignoring the rectification of a planning violation is never a money-saving measure. On the contrary, this ostrich strategy can cost you much more than the initial investment of €1,500 to €5,000. Between hefty administrative fines, depreciation of your property, and legal risks, the price of inaction far exceeds that of compliance.
The Territorial Development Code (CoDT) in Wallonia and the CoBAT in Brussels provide for a system of administrative fines proportional to the severity of the offense. The amounts start at €250 for minor offenses, but can rise to €25,000 for the most serious violations.
Aggravating factors include: repeat offenses, impact on the neighborhood, location in a protected area, refusal to cooperate with the authorities, or the dangerous nature of the construction. A simple unauthorized extension of 15 m² can cost you between $500 and $2,000 in fines, while illegally dividing a single-family home into several apartments without a permit can result in the maximum fines.
For your information:
| Type of offense | Fine range | Aggravating factors |
|---|---|---|
| Small jobs (carport, terrace) | $250 - $1,000 | Recidivism, protected area |
| Front opening | $500 - $2,500 | Front facade, listed building |
| Unauthorized extension | $1,000 - $5,000 | Large surface area, impact on the neighborhood |
| Change of destination | $2,000 - $10,000 | Division into multiple dwellings |
| Construction without a permit | $5,000 - $25,000 | Dangerousness, refusal to regularize |
The penalty process follows an administrative escalation: notification of the violation, notification to the owner, formal notice to comply within a given period (usually 6 months to 1 year), then imposition of a fine in case of inaction. These fines are in addition to the compliance costs that you will have to pay anyway.
An unresolved urban planning violation becomes a burden when selling real estate. The seller hasa legal obligation to disclose any urban planning non-compliance in the deed of sale. Attempting to conceal the violation constitutes a hidden defect for which you will be liable for 10 years after the transaction.
The concrete consequences:
Example with figures: A house valued at €300,000 with an unauthorized 25 m² extension can lose between €30,000 and €60,000 in value. Even after deducting the €3,500 cost of regularization, the owner loses between €26,500 and €56,500 due to simple negligence.
If administrative fines are not sufficient to bring about compliance, the administration may initiate legal proceedings with much more serious consequences.
The restoration order is the most feared penalty: the court can force you to demolish the offending part or restore the property to its original condition, all at your expense. The costs of demolition and reconstruction far exceed those of simple regularization. An annex that would have cost €3,000 to regularize may require €15,000 to €30,000 for demolition and restoration.
In the event of persistent refusal to comply with the repair order, the administration may have the work carried out automatically and charge you the cost plus administrative fees, with the possibilityof a daily penalty of €50 to €500 per day of delay.
| Scenario | Immediate Regularization | Non-Regularization |
|---|---|---|
| Direct cost | $1,500 - $5,000 | $0 (temporary) |
| Administrative fines | 0 € | $250 - $25,000 |
| Loss of property value | 0 € | 10% - 30% of the price |
| Risk of demolition | 0 € | $15,000 - $50,000 |
| Legal fees | 0 € | $2,000 - $10,000 |
| Blocking during sale | No | Yes (delay + discount) |
| Stress and uncertainty | Resolved in 3-12 months | Permanent |
| TOTAL over 5 years | $1,500 - $5,000 | $20,000 - $100,000+ |
The conclusion is clear: the cost of not regularizing your situation always far exceeds the investment required to bring it into compliance. Regularizing your situation quickly means choosing legal certainty, preserving the value of your property, and sleeping soundly at night.
With UBEX, turn this obligation into a stress-free process thanks to transparent support and fairly calculated rates.
Contact UBEX today for a free consultation!
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