Roof renovation is one of the most common types of work in Brussels. Whether it is a simple replacement of the roof covering, insulation, adding dormers or raising the whole roof, you may or may not need a planning permit depending on what the work involves.
Do you need a permit for roof work?
A planning permit is required when the work involves:
- A change to the volume of the building (raising the roof, adding dormers)
- A change of roofing material visible from the public space
- New openings in the roof (Velux or other roof windows) visible from the public road
- A significant change to the pitch or shape of the roof
Roof work exempt from planning permission
Under the Order of 13 November 2008 (works exempt from a permit), the following are exempt from planning permission:
- External insulation of a pitched roof, provided the roofing materials and colours are kept and the work does not reduce the glazed area
- Changing the covering of a flat roof, including raising it to add insulation or a non-accessible extensive green roof
- Like-for-like replacement of the roof covering (same materials, colours and shapes)
- Installing solar panels that are not visible from the public space
These exemptions do not apply if the property is less than 20 m from a protected heritage site.
Renovating or redoing your roof
For a standard roof renovation, everything depends on what changes:
- Like-for-like replacement of the roof covering (same materials, colours and shapes): exempt from planning permission, including a complete re-roofing
- Change of material or colour visible from the public space (for example, switching from tiles to slates): permit required
- Major repairs affecting the roof structure (replacing purlins, altering the load-bearing structure): permit required, with an architect
- Flat roof: changing the covering is exempt, including a limited increase in height to add insulation or a non-accessible extensive green roof
In practice: if your roofer replaces the covering without changing either its appearance or the structure, no planning formalities are needed. As soon as the visible appearance or the roof structure changes, go through your municipality’s planning department.
Raising the roof
Raising a roof means lifting the roof structure or reshaping the roof profile to gain an extra storey or turn the loft into living space. In Brussels, it always requires a planning permit: it changes the volume of the building and is not covered by any exemption in the Order of 13 November 2008.
Specific points to watch:
- Architect mandatory: raising the roof affects the building’s load-bearing structure
- RRU envelope rules: the new profile must fit within the rules of the RRU (Regional Urban Planning Regulation), in particular in relation to the profiles of the neighbouring roofs. Going above the highest neighbouring profile requires a derogation, which is rarely granted without solid justification
- Timeframes: 75 days from the acknowledgement of a complete application, or 160 days if the project needs a derogation or additional opinions (see permit timeframes)
- Public inquiry possible if the project departs from the RRU or from a PPAS (special land-use plan)
A successful roof raise is prepared early: ask your municipality for the planning information (renseignements urbanistiques) before drawing up the project, so you know what building envelope is acceptable on your plot.
Do you need an architect?
If the work is exempt from planning permission, it is automatically exempt from the architect requirement too. For work that needs a permit, an architect is required unless the work raises no structural issues (e.g. replacing roof window frames without structural work).
Roof insulation in Brussels
Roof insulation is a priority in the Brussels-Capital Region to improve the energy performance of buildings. There are two cases:
- Internal insulation: interior work exempt from planning permission (no change to the external appearance)
- External insulation (sarking): exempt if the materials and colours are kept and there is no derogation from the RRU (watch out: if the roof rises above the highest neighbouring roof profile, a permit will be needed)
Energy and renovation grants
The Brussels-Capital Region offers energy grants (Renolution) for roof insulation:
- Basic grant for roof insulation: the amount varies with income and the performance achieved
- A bonus is possible if the work is part of a full renovation
- The grants can be combined with some municipal grants
See renolution.brussels for up-to-date amounts and eligibility conditions.
Practical steps
- Check with your municipality’s planning department whether your work requires a permit
- If a permit is required, hire an architect to put the application together
- Submit your Renolution grant application before or during the work
- Have the work carried out by a registered contractor
- Keep all invoices for the grant application