Advice · Extension
Balcony or terrace: gaining living space outdoors
8 October 2026 · 4 min read · By the Aldeak team
A balcony or terrace extends the house outdoors and matters a great deal to buyers. But the planning rules must be respected and the construction done with care, as a poorly designed outdoor space ages quickly.
Ground-level terrace, raised terrace, balcony
The permissions required depend on the type of structure:
Laid at ground level, with no significant raising, it creates no ground footprint. Except in a protected area (surroundings of a historic monument, heritage site) or where the local urban plan provides otherwise.
It creates ground footprint: a prior declaration, or even a building permit depending on the area created.
It alters the façade: a prior declaration, or even a building permit depending on the area created.
Find out first
- The local urban plan: distances from boundaries, external appearance, permitted materials.
- Views over the neighbour: the French Civil Code sets minimum distances for direct and oblique views.
- The co-ownership, where applicable: the agreement of the general meeting is required to alter the façade.
Safety
Wherever there is a risk of falling, a guardrail is essential. Its height and strength meet a precise standard, and it must prevent a child from climbing over it. For a balcony, the structure (slab, brackets, anchorages in the wall) has to be calculated: it is structural work, not a simple fitting-out.
The right materials
- Wood: warm, to be chosen in a durable or treated species, with regular maintenance.
- Composite: little maintenance, but it gets hot in the sun.
- Stone or outdoor tiles: durable, to be laid on a slab with a drainage slope.
In every case, water drainage and waterproofing where the structure meets the house are what make it last.
Views over the neighbour: precise distances
A balcony or raised terrace creates a view over the neighbouring property. The French Civil Code sets the distances: a direct view (facing the neighbouring land) is only allowed at least 1.90 m from the property boundary, an oblique view (at an angle) at least 0.60 m. These distances are measured from the outer edge of the balcony or terrace.
A raised terrace built too close to the boundary may have to be set back or closed off with a fixed, opaque privacy screen, even if the planning authority accepted it: the prior declaration is granted “subject to the rights of third parties”.
The guardrail: the benchmarks of the standard
The French standard NF P01-012 sets the height of a guardrail at no less than 1 m in the usual case, measured from the finished floor of the terrace. So that a child can neither slip through nor climb up, the gap between balusters is limited to 11 cm, and the bottom of the guardrail must offer no foothold (horizontal rails at the bottom form a ladder).
A glass or tensioned-cable guardrail must follow the same rules: appearance is no excuse for compromising on safety.
Worked example: a 20 m² raised terrace
Take, by way of example, a house whose living room is 1 m above the garden. The owners want a 20 m² wooden terrace level with the living room.
| Ground footprint created | 20 m² |
| Permission | prior declaration, below the building permit threshold |
| Processing time | one month, two months in a protected area |
| Development tax | none: being neither enclosed nor covered, the terrace creates no taxable floor area, unlike a conservatory |
On the other hand, it needs a guardrail on the sides exposed to a drop, a frame sized for the loads of a terrace in everyday use, and sufficient set-back from the neighbour if it overlooks their property.
The stages of a project
- Check the local urban plan and the distances from property boundaries.
- Choose the location: orientation, wind, privacy, access from the kitchen or living room.
- Have the structure drawn up and calculated (slab, posts, anchorages).
- Submit the prior declaration or the permit application, with plans and a landscape integration document.
- Build, taking great care over waterproofing and water drainage along the house.
- Declare completion of the works at the town hall.
Mistakes to avoid
- Laying the terrace against the wall without precautions: water standing at the foot of the façade ends up rising into the walls.
- Fixing a balcony to a wall that cannot bear it: an old rubble-stone wall or hollow masonry requires a survey before any anchoring.
- Forgetting the slope: a flat terrace floor holds water, freezes in winter and ages quickly.
- Choosing wood unsuited to outdoor use: the wrong species or treatment rots within a few years.
Our expertise
We design and build terraces, balconies and outdoor spaces, taking care of the planning formalities and coordination with the other work on the house.
Sources : Code civil, articles 678 et 679 (distances des vues droites et obliques) · Code de l’urbanisme, articles R. 421-14 et R. 421-17 (seuils de la déclaration préalable et du permis de construire) · Code de l’urbanisme, article R. 423-23 (délais d’instruction) · Norme NF P01-012 (dimensions des garde-corps) · Agence Qualité Construction, fiche « Garde-corps : protection contre la chute, l’escalade et le passage » · service-public.gouv.fr, taxe d’aménagement (terrasses non taxables) · Loi n° 65-557 du 10 juillet 1965, article 25 (travaux touchant les parties communes ou l’aspect extérieur)
Frequently asked questions
Do you need permission for a ground-level terrace?
Generally not, except in a protected area or where the local urban plan has a specific rule. Check with the town hall.
Do you need permission to build a balcony?
Yes: a balcony alters the external appearance, so a prior declaration at the very least is required.
Is a guardrail compulsory?
Yes, wherever there is a risk of falling. Its height and strength are set by a standard.
How high should a terrace guardrail be?
At least 1 m in the usual case under the French standard NF P01-012, with balusters no more than 11 cm apart.
How close to the neighbour can you build a balcony?
A direct view is only allowed at least 1.90 m from the property boundary, an oblique view at 0.60 m (French Civil Code, articles 678 and 679).
Is a terrace subject to the development tax?
Not if it is neither enclosed nor covered. A conservatory or an enclosed terrace, on the other hand, creates taxable floor area.
Wood or composite for a terrace?
Wood is warmer but needs regular maintenance; composite needs little but gets hot in the sun. The choice depends on the exposure and how much time you want to spend on it.
