In a condominium, the difficulty is not technical: it is legal and collective. The roof is a common part, the decision is taken at the general meeting, and the output then has to be shared between households that do not consume at the same time. This page sets out the whole path, from putting the item on the agenda to the grid connection, and flags what changes depending on whether you are in Wallonia, Flanders or Brussels.
Energy sharing within a single building is now governed by precise rules in Wallonia and in Brussels, opening the way to the energy communities. Yet between the majority rules at the general meeting and the technical allocation of the green certificates, installing solar panels in a Belgian condominium often looks like a genuine administrative challenge. Your project risks stalling on your neighbours' hesitations or on uncertainty about the financing.
This article clarifies the current legal framework and the ways in which the costs are shared, to help you carry out your collective installation with peace of mind. We go through the key stages, from the co-owners' vote to the management of the meters.
The legal framework for solar panels in a Belgian condominium
In Belgium, a photovoltaic installation in a condominium requires a majority of 50% plus one vote, or two thirds depending on the intended use. The roof remains a common part, which means formal approval at the general meeting for any private or collective connection, because the validity of the project depends on the vote.
Obtaining approval from the general meeting of co-owners
The vote requires 50% of the votes plus one where the common interest is concerned. To alter the common parts, the majority rises to two thirds. Strictly observing the quorum remains essential during the meeting.
You need to ask the managing agent to put your project on the agenda. This request is usually made when all the owners of the building are convened for the annual meeting.
50% + 1 vote for projects in the common interest, against a majority of 2/3 for structural changes to the common parts.
During the vote, draw a clear distinction between the collective project and strictly private use. Always make sure that your request complies with the rules governing your particular condominium.
Right to use the roof and the definition of the common parts
Check your deed of co-ownership to confirm the legal status of the roof. These common parts belong jointly to all the co-owners, which limits any isolated personal initiative.
An exclusive right of use never replaces a building permit. You therefore cannot install your modules without first obtaining the explicit consent of the condominium.
Insurance remains a strict obligation for everyone. Any connection changes the safety of the building.
Who pays and who benefits from the energy produced?
With the legal side secured, it is now time to look at the money and the way the electrons are shared between neighbours.
Splitting the installation costs between the different units
The financing is based on your shares in the condominium. Each owner contributes in proportion to the shares set out in the deed of co-ownership. That is the standard accounting rule.
Co-owners who refuse the investment are left out. Only those who pay actually benefit from the solar electricity produced.
To get your project started, request a personalised solar study. Your managing agent then handles the specific calls for funds.
The inverter remains collective. Maintenance is shared between the participants.
Wallonia and Brussels now govern energy sharing within a single building through the energy communities.
Collective self-consumption and lower common charges
The energy first powers the shared equipment such as the lift or the lighting in the entrance hall. That mechanically reduces your monthly provisions for common charges.
- Sharing between flats
- Injection of the surplus
- Lower individual bills
- Optimisation with a battery
The unused surplus is put to good use. This electricity is sold to the energy supplier that your managing agent has previously selected.
Technical management of the meters and the distribution grid
Sharing the money relies on a precise technical architecture, coordinated by the local grid operators.
Connection and the role of the distribution grid operator
You must declare your installation to the relevant grid operator, such as Ores, Resa or Sibelga. The connection requires formal approval before the system is actually commissioned.
Injection takes place through a single point for the whole building. To assess your project, use this simulator in order to anticipate the technical requirements of this collective set-up.
Compliance with fire safety standards remains an absolute priority. An approved inspection body must certify that your equipment conforms.
Provide the mandatory single-line diagram. This technical document is crucial for your file to be approved.
Metering and allocation of the electricity produced
The smart meter improves on the classic bidirectional model by automating the readings. It allows the index to be read remotely, without constant intervention on site.
| Criterion | Classic meter | Smart meter |
|---|---|---|
| Meter reading | Manual | Remote |
| Surplus management | Manual | Automated |
| Cost | Low | Higher |
| Accuracy of the sharing | Estimated | Real time |
Allocation often relies on precise energy management software. Your managing agent thus coordinates the flows between the different units.
The green certificates support the financial balance. They give value to the output in Brussels and in Wallonia.
Regional specifics and the case of a rented home
Finally, the success of your project depends on where you are located and on your status as an occupant.
Regulatory differences between Wallonia and Brussels
The rules on the energy communities differ from one region to another. Brussels favours local sharing through simplified structures. Wallonia follows its own separate legislative framework.
The certification procedures also vary. The forms and the deadlines depend on the competent regulator. You will deal with CWaPE or with BRUGEL depending on your address.
Wallonia: CWaPE (energie.wallonie.be). Brussels: BRUGEL (brugel.brussels).
For any question about support schemes in Belgium, see our dedicated page. It brings together the useful information.
Consult the official regional websites. Each energy portal sets out its own technical specifics.
Impact of a solar installation on the lease
The relationship between landlord and tenant must be clear. The owner pays for the technical equipment. The tenant benefits directly from lower electricity bills.
Check your charge provisions. A contractual revision often proves necessary. It allows the lease to reflect the energy savings achieved day to day.
Update your energy performance certificate after the works in order to improve the property's energy score.
Make the most of your energy performance certificate. A photovoltaic installation improves the overall energy score. That mechanically increases the rental value of your property.
By mastering the legal framework and the vote at the general meeting, you add lasting value to your property. Start energy sharing between neighbours now to reduce your common charges and your individual bills with solar panels in a condominium in Belgium. Turn your building into a source of clean, profitable energy today.
What about financial support?
Support for photovoltaics is regional and it has changed a great deal: what applies in Brussels applies neither in Wallonia nor in Flanders. We therefore publish no figures in this article. The scheme that applies in your region, with its official source and its verification date, is on our Belgium page.
