Installing solar panels without checking planning regulations can turn an ecological gesture into a costly offence.
In Belgium, certain residential solar projects require planning permission or prior declaration, depending on the location, height or layout of the installations. Solar panel authorizations vary depending on the region, whether the installation is on the facade or the roof, and the architectural constraints of the property.
This article untangles the conditions under which a permit is required, the steps to take and the common mistakes to avoid, both in Brussels and in Wallonia. A clear resource for securing your photovoltaic installation and avoiding any emergency regularization.
In Belgium, town planning is the responsibility of the regions. This means that the rules governing the installation of solar panels vary depending on whether you're in Wallonia, Brussels or Flanders.
Each region has its own code: the Code du Développement Territorial(CoDT) in Wallonia, the Code Bruxellois de l'Aménagement du Territoire(CoBAT) in Brussels, and the Vlaamse Codex Ruimtelijke Ordening(VCRO) in Flanders.
These texts define when planning permission is required and when it is not. In addition, there are often specific rules at municipal level, such as planning regulations or guides, which supplement the regional regulations.
In Wallonia , article R.IV.1-1 of the CoDT mentions various cases in which a solar installation is exempt from the permit requirement, provided certain restrictions are met.
In Brussels, the rules distinguish between installations that are visible from the public space and those that are not, with a more flexible exemption system for the latter.
In Flanders, the VCRO also provides for exemptions based on criteria such as aesthetics, size or location.
Criteria vary between the three regions: visibility from the public space, impact on the building, location on the ground or on the roof, type of property concerned, etc. Additional requirements may apply to buildings located in protected or heritage areas. Additional requirements may apply to buildings located in protected or heritage areas.
Photovoltaic panels generate electricity from solar energy, while thermal panels use this energy to heat water or a heat transfer fluid. This technological difference is more than just a detail: it influences the legal conditions that apply.
Some regulations cover only photovoltaic panels, while others encompass both technologies under the term "solar systems". This distinction can have an impact on the planning assessment of a project, particularly with regard to its architectural integration or visual effect.
Related content: Attic conversion: do I need planning permission?
In Wallonia, the conditions for exemption are clearly set out in the CoDT. To qualify, the system must be installed on an existing home, respect the slope of the roof (with a maximum overhang of 30 cm), maintain a color similar to that of the roof, and not be visible from the public highway in sensitive areas (classified or protected zones).
In addition, the installation must not alter the architectural appearance of the building.
For ground-mounted devices, an exemption is possible if the surface area does not exceed 20 m² and if no structure creates a free-standing built volume.
Antoine HORENBEEK
In Brussels, installations on flat roofs, set back and invisible from the street, generally benefit from automatic exemption from permits, provided certain conditions are met: no modification of the building's structure, maintenance of the existing gauge, and discretion of the addition in relation to the architectural character of the property.
This policy aims to encourage the installation of panels while preserving the quality of the urban environment.
In Flanders, too, the installation of panels is often exempt from permits when they follow the slope and orientation of the roof, without extending beyond its edges.
Ground-mounted installations may be exempt if their surface area is less than 40 m² and their height does not exceed 3 meters, provided they are well integrated into their surroundings. Stricter rules apply to protected or listed buildings.
As soon as the panels are visible from the street or installed on the facade, a permit is often required, especially in heritage or protected areas.
This rule is designed to avoid any unsightly alteration of public space or a site of historical value. Apartment buildings are also subject to stricter control, as their transformation may affect the entire architectural volume.
If the panels require reinforcement of the roof structure, a change of roof covering or a hole in the roof, we're no longer talking about "simple installation".
These are structural works subject to planning permission, even if the installation remains discreet on the outside. Any change to the volume or integrity of the building requires authorization.
Installing panels on a garage, annex, warehouse or agricultural shed does not automatically exempt you from obtaining a permit.
These constructions may be located in areas where town planning regulations impose stricter constraints. The destination of the site, its use for town planning purposes or its location outside a residential area may make planning permission compulsory, even for small-scale installations.
When panels are installed on the ground to a significant extent, rise several meters or are installed on rigid structures, they can be considered as built volumes.
This is particularly true in agricultural and rural areas, where visual impact and soil artificialisation are decisive factors in urban planning assessments. In such cases, a permit is generally required to ensure proper integration into the landscape.
An installation carried out without a permit, when it was essential, constitutes an urban planning offence.
It exposes the owner to a series of sanctions: fines, the obligation to regularize the work, or even demolition imposed by the authorities.
In Wallonia, reinstatement can even be ordered by a judge if regularization is refused or non-conformity is confirmed.
Antoine HORENBEEK
A building in breach of the law can cause problems when it comes to selling. Notaries, real estate agents and buyers often check urban planning compliance before finalizing a transaction. An illegal installation can derail a sale, reduce the value of the property, or delay the granting of a mortgage. Banks take any irregularities into account when assessing risk.
In the event of unauthorized installation, insurers may refuse to intervene in the event of a claim, particularly if the cause is linked to the installation or operation of the panels. An exclusion clause may come into play, leaving the owner to bear the costs alone.
In the event of damage to others, civil liability may also be incurred for installing undeclared or poorly-integrated equipment on a building.
Prevention is better than demolition. When it comes to town planning, even something as simple as solar panels may require a permit, depending on your situation.
To clarify your case, avoid penalties and regularize what can be, talk to us now. At Ubex, our team of experts will take over, so you can move forward with peace of mind.
Author : CORNIL Olivier
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