Works: when do you need planning permission?

Wallonia: a list of works requiring a permit

The CoDT (Book IV) lists the acts and works that require a permit. According to wallonie.be, they include for example:

• building or placing fixed installations;
• putting up signs or advertising;
• demolishing, rebuilding or converting an existing building;
• changing the use of a property;
• creating a new dwelling in an existing building;
• significantly altering the ground level;
• felling protected trees or hedges.

SPW Territoire (the Walloon public planning service) explains the logic: if the works are not included in the list in article D.IV.4 of the CoDT, they are not subject to planning permission. Then article R.IV.1-1 distinguishes three levels: works exempt from permission, works with limited impact (a simplified permit, often without an architect) and those requiring a full permit.

In most cases, it is the municipal executive (collège communal) that grants the permit. The time limit given by wallonie.be ranges from 30 to 115 days, depending on the procedure, from the moment the application is declared complete.

Wallonia: examples of exempt works

The official SPW Territoire table gives examples. It dates from the 2021 update: the exact conditions may have changed, check the version in force.

• Garden shed or outbuilding: only one per property, in the courtyard and garden area, with in particular a maximum floor area of 20 m², a distance of at least 1 m from the shared boundaries and maximum heights of 2.50 m to the gutter and 3.50 m to the ridge.
• Small extension: a single secondary volume with a footprint of 40 m² at most, at least 2 m from the shared boundary, with materials of a similar tone.
• Conservatory: up to 40 m², if all the conditions in the table are met. Above 40 m², a full permit with an architect is required.
• Insulation and cladding: placing or replacing façade or roof materials to meet energy standards, in particular if the new element adds no more than 0.30 m of thickness.
• Solar panels: see the guide on solar panels.

The SPW states that the exemptions apply even where there is a departure from an indicative document, unless the conditions on the line expressly require compliance with the rules in force. Read the line that concerns you.

Brussels: the permit is the rule

According to the Region, construction, demolition and conversion works, “interior as well as exterior”, in principle require prior planning permission. The exemptions are defined exhaustively by the Government decree of 13 November 2008 (amended by the decree of 17 March 2022). They only apply if the works do not breach planning regulations: special land-use plan (PPAS), regional planning regulation (RRU), municipal regulation (RCU).

The Region explains that exempt works generally have no impact on the stability of the building, and do not change its volume, its appearance as seen from the public space, its use or the number of dwellings.

Examples of exempt works in Brussels

• Interior conversions and fittings: renovating a room, building or demolishing a light partition, electrical, plumbing or heating work, replacing a floor covering, interior insulation. Condition: not affecting stability, nor changing the number or layout of dwellings.
• Changing the use of a room within a dwelling: for example a living room that becomes a dining room, as long as the rooms remain used for housing.
• Liberal profession ancillary to the main residence: up to 75 m², or between 75 and 200 m² if it occupies at most 45% of the total floor area of the dwelling.
• Replacing window frames like for like: shapes, divisions, opening and fixed parts kept. Switching from a white wooden frame to white PVC still requires a permit, even if the appearance is identical.
• Insulating a pitched roof from the outside, subject to conditions (materials and colours kept, no loss of glazed area, property more than 20 m from a protected property).
• Photovoltaic panels not visible from the public space.
• Garden shed not intended for habitation, in the courtyard and garden area: 9 m² at most, 3 m high at most.
• Demolition of an annex of less than 100 m² not visible from the public space, subject to conditions.
• Terraces, paths and fences in the courtyard and garden area: limited heights (1.5 m at the shared boundary, 1 m in the setback area).

Some works still require a permit but are exempt from the opinion of the delegated official, of certain bodies, from public notice measures or from the involvement of an architect. The examples above concern non-protected properties; several exemptions no longer apply within 20 m of a protected property.

For works that require an architect in Brussels, the Region cites for example: an extension or a conservatory, opening up a load-bearing wall, creating or moving a stairwell.

Energy works and the permit

Energy requirements (EPB) and the permit often go together in Brussels: see the EPB renovation obligation. In Wallonia, the housing audit comes before the grants: see the housing audit.

Which professional to consult

Your commune’s planning department is the first point of contact: it tells you whether your project is exempt. An architect prepares the file when one is required. A surveyor (géomètre-expert) can draw up a plan, see the land surveyor.