Are you renovating in Brussels and working on the roof, walls, floor or windows? You will almost certainly face the EPB requirements. Discover the essential obligations and key points to monitor to avoid unnecessary expenses.
The EPB requirements (Energy Performance of Buildings) have several aspects. Here, we focus on insulation: when do the rules apply, what are the key principles, and why they are beneficial for you. For exact thresholds and exceptions, consult the official information from Brussels Environment.
Who do the EPB obligations apply to?
The EPB rules apply to all buildings with heating or air conditioning where construction, renovation or reconstruction works are carried out and require a planning permit. This concerns new construction, reconstruction or major renovations.
Important: The requirements apply when you modify the external envelope (roof, façade, floor or windows), as this affects the building’s energy performance.
There are, however, some exceptions, such as places of worship, certain agricultural buildings or small non-residential buildings.
New context: Renovation obligation in Brussels (2033–2045)
By 2033 and then 2045, homes will have to meet specific energy performance targets (kWh/m²). The EPB requirements during renovations help you achieve these targets.
Here are the main principles. The exact thresholds of EPB requirements depend on the nature of the works and the building’s purpose.
Limit thermal bridges
A thermal bridge is a point where heat escapes easily because insulation is interrupted, for example at junctions between wall and floor or at the roof level. Thermal bridges not only cause heat loss but also increase the risk of condensation and mould.
It is essential to ensure maximum continuity of insulation at points where different elements meet. This continuity prevents heat loss to the outside. Structural joints must therefore have a low linear thermal transmittance coefficient.
Annex V of the EPB decree of 5 May 2011 (and its amendments) sets the limit values for this coefficient.
Insulating the building shell
The EPB requirements impose maximum U-values for the different parts of the external envelope.
- U-value: amount of heat passing through an element per m² for a temperature difference of 1°C. The lower the U-value, the better the insulation.
- R-value: thermal resistance of a material or construction. The higher it is, the better the insulation.
For roofs and external walls, these values generally correspond to 18 cm of glass wool or 20 cm of wood fibre.
There is no obligation regarding the type or thickness of the insulating material, as long as the required performance is met.
Reduce energy consumption
The EPB regulations also impose measures that directly impact insulation, the choice of techniques and the use of renewable energy:
- Reduce the net energy need for heating for dwellings.
- Limit primary energy consumption for heating, domestic hot water, air conditioning and auxiliaries.
- Ventilate rooms according to flow rates to ensure a healthy indoor climate and intensive ventilation in case of overheating or pollution.
- Reduce the risk of overheating.
And if I do not comply with these obligations?
If you do not comply with the EPB requirements, you risk fines of several thousand euros.
It is also in your interest to comply with these requirements, or even do better.
- Most energy grants impose stricter conditions than the legal minimum.
- Good insulation directly increases the rental or sale value of your home.
- You save on expenses and contribute to a more sustainable society.
- You have a head start on the future, stricter legislation.
Strengthening your insulation is therefore a smart decision at every level.