A conservatory built in the 1990s, a converted attic, a house split into two flats… In Brussels, old works like these resurface when it is time to sell. The document that reveals them is the urban planning information certificate (renseignements urbanistiques). Brussels makes it mandatory for every sale, and what it says can delay a preliminary agreement, lower an offer or put a buyer off. The good news: most hold-ups can be avoided if you start early.
Here is how to obtain urban planning information in Brussels, what it contains, the most common breaches and how to deal with them before you put your property on the market.
Urban planning information is, in a sense, the planning identity card of a property. Issued by the municipality, it states in particular:
- the property’s designated use (housing, office, retail…);
- planning permits and certificates granted or refused;
- any recorded breaches and the action taken on them;
- heritage protection or pre-emption measures.
The application includes a short description of the property, with a plan of its current layout and a photo of the façade. The municipality compares this description with its file and may flag discrepancies. It does not visit the property, and it does not guarantee that its file is complete.
Who applies, how long does it take, what does it cost?
The seller, their notary or their agent can submit the application. It is increasingly done online, via Irisbox or the notaries’ platform.
The legal deadline is 30 calendar days after a complete application is received. In practice it is often exceeded, sometimes by several months depending on the municipality. The fee also varies by municipality: in Etterbeek, for example, an application costs €103.70, or €207.40 for an urgent request (source). Check your own municipality’s fee.
This information must appear in the advertisement and be given to prospective buyers before signing, as notaire.be points out. It comes on top of the other mandatory documents (EPC, electrical inspection, soil certificate…) listed in our checklist of mandatory documents.
The most common planning breaches in Brussels
A discrepancy between the description and the municipal file does not prove a breach. Some works did not require a permit at the time. But four situations come up again and again.
A conservatory or rear extension. It changes the building’s volume and generally requires a permit. Many were built without one.
A converted attic or cellar. Turning an attic into a bedroom, adding a dormer or a terrace may require a permit, especially if the façade or volume changes.
Division into several units. This is the typical Brussels breach: a single-family house split into flats without authorisation. We tell its story in the mystery of divided Brussels houses. The number of authorised units has a direct effect on the property’s value.
Window frames and façade. Replacing wooden frames with PVC, or changing their divisions or colour, may require a permit, particularly for a protected property or one in an area of cultural interest. This is common in the heritage-rich neighbourhoods of Ixelles, Uccle and Forest.
Planning breaches and your sale: what changes
A breach does not make a sale impossible. But the buyer must know about it, as early as possible.
- The buyer must be informed. The seller must disclose any breach before signing. The preliminary agreement then states who handles the regularisation, and on what terms.
- The price is affected. A buyer factors in the cost, time and uncertainty of a regularisation. Two unauthorised attic bedrooms are not worth the same as two compliant ones.
- The timeline may slip. If the information is late, the seller can only state the date of the application, and the notary may postpone the deed. The steps are described in our guide from preliminary agreement to notarial deed.
- Financing may be affected. A bank may take an irregularity into account when valuing the property.
Beware of a common misconception: an old breach is not thereby “regularised”. The limitation period concerns criminal prosecution. Administratively, the property may remain irregular, and the municipality can still require a permit application or restoration to the original state.
Regularise or sell as is?
There are three options. The right choice depends on the breach, the market and your timeline.
1. Clear up the discrepancy
Sometimes there is no breach at all: the works did not require a permit at the time. With evidence (dated photos, old plans, deeds), you can demonstrate this to the municipality, which then issues corrected information (Cambier Avocats).
2. Apply for a regularisation permit
This is the safest route to selling at the best price, but it takes time and an architect. For works carried out before 1 January 2000, a simplified procedure exists (Article 330 §3 of the CoBAT), provided the works comply with the rules in force at the time or today. Prior advice from the fire service (SIAMU) is then required (be.brussels).
3. Sell as is, with full transparency
If regularisation is lengthy or uncertain, you can sell the property as is. The breach is then clearly described in the advertisement and the preliminary agreement, and the price reflects it. This option suits investor buyers or renovation projects.
In every case, make this choice with your notary and, if needed, an architect.
- Apply for urban planning information as soon as you consider selling, without waiting for a buyer.
- Write an honest, complete description: number of units, bedrooms, extensions, attic.
- Gather your records: old permits, plans, dated photos, purchase deeds.
- Consult the planning file at the municipality if in doubt.
- Compare the municipality’s answer with the reality of the property.
- If there is a discrepancy, have it assessed by an architect and your notary.
- Decide: clear up the discrepancy, regularise or sell as is.
- Inform prospective buyers from the first viewings.
Frequently asked questions
Is urban planning information mandatory to sell in Brussels?
Yes. It must appear in the sale advertisement and be given to the buyer before the preliminary agreement is signed. The notary also includes it in the deed.
How long does it take to obtain?
The legal deadline is 30 calendar days after a complete application. In some municipalities it is often exceeded, so it is best to apply as soon as your sale plans take shape.
How much does urban planning information cost?
The fee depends on the municipality. In Etterbeek, for example, an application costs €103.70, or €207.40 for an urgent request. Each municipality sets its own amount.
Can you sell a house with a planning breach?
Yes, provided the buyer is clearly informed. The preliminary agreement then states who handles the regularisation and on what terms, and the price reflects it.
Is a very old breach automatically regularised?
No. The limitation period concerns criminal prosecution, not the administrative status of the property. For work carried out before 1 January 2000, however, a simplified regularisation procedure may apply, subject to conditions.
Conclusion
Urban planning information in Brussels is not a mere formality: it shapes the price, timing and peace of mind of your sale. Requesting it early keeps you in control of the timeline and the negotiation.
Thinking of selling in Uccle, Ixelles, Forest or elsewhere in Brussels? GR Properties reviews your property’s planning situation and factors it into its valuation. Request a valuation of your property.
