Procedures · Read 8 min
Do you need a town-hall permit to install AC in France?
By the Aircadia team
Yes, fitting an outdoor air-conditioning unit that changes the exterior appearance of a building is, in principle, subject to a prior works declaration at the town hall (Cerfa 13703 form, article R*.421-17 of the French urban planning code). A decree of 20 February 2026 now exempts installations on a façade not visible from the street, from a public way or from another building — except in protected areas, a frequent case in Nice.
The essentials
- Cerfa 13703 at the town hall whenever an outdoor unit is visible.
- New in 2026: exemption if the unit is visible neither from the street, nor from neighbours, nor from any public way.
- Old Nice, monument surroundings, listed sites: the exemption does not apply, and the French Buildings Architect (ABF) must give an opinion.
- Instruction time: 1 month in a standard area, 2 months in a protected zone.
Do you really need a prior declaration to fit AC?
The rule is simple: as soon as fitting an outdoor unit changes the exterior appearance of an existing building (façade, roof, street-facing wall, visible balcony), article R*.421-17 of the French urban code requires a prior works declaration at the town hall. It applies to single-family houses as well as flats.
Do not confuse the two tracks: the prior declaration is a matter of urban planning — the town hall handles it. It is separate from the co-ownership general meeting’s approval, which is a matter of co-ownership law. Both can stack up for a flat (see our dedicated guide on co-ownership approval).
What did the decree of 20 February 2026 change?
Published in the Journal officiel of 21 February 2026 and in force since March 2026, decree n° 2026-117 (article 16) amends article R*.421-13 of the urban code and exempts from any formality works fitting a heat pump on a façade « that is visible neither from the public domain, nor from a public way, nor from another building with a view of the installation ».
In practice, an outdoor unit placed in an enclosed inner courtyard, at the back of a house invisible from the street and without direct overlook, no longer needs a prior declaration. A reversible split (technically an air-to-air heat pump) logically falls under the same regime, provided the non-visibility condition is met.
The exemption does not apply in several cases that are common on the Riviera: outstanding heritage site, historic monument listed or classified, the surroundings of a historic monument, a classified or being-classified site, a natural reserve, or a building protected under the local urban plan (PLU).
How to tell whether your project goes through the town hall or not
The table below sums up the main situations found in the Alpes-Maritimes.
| Situation | Urban-planning formality | Instruction time |
|---|---|---|
| Outdoor unit visible from the street, standard zone | Prior declaration (Cerfa 13703) | 1 month |
| Unit in an inner courtyard, unseen by neighbours or street | None (decree of 20/02/2026) | — |
| Visible unit in an ABF-protected area (Old Nice, near listed monuments) | Prior declaration + ABF opinion | 2 months |
| Outstanding heritage site, classified or listed monument | Prior declaration (no exemption) | 2 months |
| Flat in co-ownership (exterior affected) | Prior declaration + AGM approval on top | Variable |
A useful reflex: ask the town hall for an informative urban planning certificate, or consult the online PLU to check whether the address falls within a protected perimeter.
Nice: why the topic is more sensitive here
Nice piles up constrained zones: the Old Nice safeguarded sector, the surroundings of many historic monuments (numerous in Cimiez, along the Promenade des Anglais and in the grand town-centre residences), and several listed or classified sites along the coast and hills. In these perimeters, the French Buildings Architect (ABF) must give an opinion and frequently refuses outdoor units visible from the street or from a protected viewpoint.
Solutions usually accepted: unit placed on an invisible roof terrace, in an inner courtyard, on a back façade out of sight, or a ducted system (outdoor unit hidden). A well-prepared file with photomontage and technical sheet sharply raises the odds of a “yes”.
How long and what paperwork for the prior declaration?
The procedure is filed with Cerfa 13703 (single-family house) or Cerfa 13404 (other buildings), submitted at the town hall or through the national online urban-planning single window. The town hall has 15 days to check completeness and 1 month to instruct (2 months in an ABF area or listed site). After that, silence means approval — but you should still obtain the written non-opposition order, useful in case of dispute.
Key documents: site plan, block plan, before-works photos, landscape insertion (photomontage of the unit in place), descriptive note with the unit’s dimensions and sound level.
What is the risk of fitting without a declaration?
An installation put in without a declaration is a breach of the urban planning code. The town hall can issue a formal notice — and, with a sworn officer’s report, launch proceedings: a fine of up to €6,000 per square metre of unlawful construction (article L.480-4), and an order to reinstate, i.e. remove the unit at your cost. Aggrieved neighbours can also sue in civil court for abnormal nuisance.
On top of that, in co-ownerships, come the risks tied to the internal rules (see our guide on co-ownership) and, if the unit is noisy, the public-health thresholds detailed in our article noise and neighbours.
FAQ — Prior declaration for air conditioning
My AC only has a small outdoor unit — am I really concerned?
Yes, as soon as it is visible and modifies the building’s exterior, size does not matter: that is the principle of article R*.421-17. A 60 × 80 cm console on a street-facing façade requires the same prior declaration as a large unit. Since March 2026, the exemption only applies if it is visible neither from the street, nor from a neighbour, nor from any public way.
Does the February 2026 decree also cover AC (and not just heat pumps)?
The text literally uses “heat pump”. However, a reversible AC is technically an air-to-air heat pump, in line with industry terminology. The exemption should therefore cover non-visible reversible AC units. For a cooling-only AC (rare today) or in case of doubt, it is safer to ask the local town hall before starting works.
How long does the prior declaration take?
One month in a standard zone, two months in an ABF area or listed site, counted from a complete file. The town hall has 15 days to ask for missing documents. Once the deadline has passed, silence means tacit approval, but we recommend asking for a certificate of non-opposition to avoid any later dispute.
What if the town hall refuses my project?
You have two months to file a gracious appeal with the mayor, then, failing that, a contentious appeal before the administrative court. A more effective route is often to file again with a revised layout (courtyard side, on the roof, integration cladding) that addresses the grounds for refusal. In Nice, refusals in ABF areas almost always target visibility of the unit: moving it is often enough.
Sources and references
- Decree n° 2026-117 of 20 February 2026, article 16 — exemption from formality for a heat pump on a non-visible façade (Légifrance, JORF n°0044 of 21 February 2026).
- Article R*.421-17 of the French urban code — works modifying exterior appearance subject to prior declaration (Légifrance).
- Prior works declaration — Service-Public.fr, sheet F17578 — procedure, deadlines and documents to provide.
A project in the 06? We secure the paperwork for you
Aircadia works in Nice, Cannes, Antibes and across the 06. Our technicians help you position the outdoor unit to benefit from the 2026 exemption whenever possible, prepare a prior declaration file readable by the urban planning department, or propose a ducted solution when ABF constraints apply. Clear, free quote within 48 h, plus our useful guides: air conditioning in a co-ownership and noise and neighbours.