PLU Cannes Zone UB: Does Your Land Coverage Ratio Exceed the Limit?

URBAN PLANNING — FRENCH RIVIERA

You bought a plot in Cannes, zone UB. You take out the tape measure, you measure the footprint of your future house: 120 m² of ground coverage. The PLU (Local Urban Plan) allows 40% of the plot, which is 300 m². 40% of 300 = 120. You are right on the limit. Yet the planning department tells you your project is non-compliant. Why? Because the land coverage ratio (coefficient d’emprise au sol, CES) is not calculated as you think. An error that can cost 6 months of procedure.

What You See — and What It Really Hides

What you measured is the ground floor area of your building. But the PLU of Cannes, in zone UB, includes in the land coverage: roof overhangs, uncovered terraces more than 0.60 m high, swimming pools, and even raised slabs. On your plot, you have a 20 m² terrace and a 10 m² awning. You don’t count them, but they count.

On a file in Cannes last year, I measured a 250 m² plot. The owner planned 95 m² of footprint. But with overhangs and a pool, we reached 115 m². That is 46% instead of the allowed 40%. Result: permit refused. What I often see: people forget the ancillary elements. And the PLU of Cannes is very strict on this point.

The Calculations That Change Everything: The Real CES According to Cannes PLU

The land coverage ratio (CES) is calculated using the formula: CES = (S_building + S_ancillaries) / S_plot × 100. But be careful: the PLU of Cannes, in zone UB, article R431-8 of the French Urban Planning Code (paragraph 2), defines land coverage as the vertical projection of all constructions, including roof overhangs, terraces more than 0.60 m high, swimming pools, slabs, and non-buried basements. Numerical example: plot of 300 m², house of 120 m², roof overhang 10 m², terrace 15 m², pool 25 m². Total footprint = 170 m². CES = 170/300 × 100 = 56.7%. The limit in zone UB is 40%. Result: non-compliant. What this means concretely: you exceed by 16.7 points, i.e., 50 m² too much. The permit will be refused.

What Happens If You Do Nothing: The Risk of Litigation

If you build without a permit or without respecting the CES, you are in violation. The Cannes city hall can demand demolition. The cost of a partial demolition? Between €15,000 and €30,000 for an extension. Not to mention lawyer fees and penalties. In 2 years, you could lose €50,000.

In the longer term, 5 years, if you sell, the notary will discover the non-compliance during the transaction. The buyer can cancel the sale or demand a discount. Developers in Cannes, like Nexity or GA Smart Building, systematically check these points. A CES non-compliance can block the sale.

Recourse and Guarantees: What You Can Demand

You can challenge a permit refusal by invoking an error in interpreting the PLU. But first, have your calculation verified by an expert. The PLU Cannes / Art. R431-8 CU (paragraph 3) provides that the CES can be modulated for limited extensions. Send a registered letter with acknowledgment of receipt to the city hall to request an operational urban planning certificate (certificat d’urbanisme opérationnel). If the refusal persists, appeal to the administrative court of Grasse. An urban planning expert can help you demonstrate that your project respects the spirit of the PLU, even if the figure slightly exceeds. But be careful: in Cannes, margins are very tight.

📅 Mis à jour le 11/08/2026 — Par Cassini Expertise, expert bâtiment indépendant 06 & 83. Devis gratuit : 04 22 46 06 04.

Questions fréquentes

What is the maximum land coverage ratio in zone UB of Cannes PLU?

In the PLU of Cannes, zone UB generally allows a maximum land coverage ratio (emprise au sol) of 50% of the plot area. However, this can vary depending on the specific sub-sector and the size of the plot, so it's essential to check the exact regulations for your property.

How is the land coverage ratio calculated in Cannes zone UB?

The land coverage ratio is calculated by dividing the total ground floor area of all buildings (including annexes) by the total area of the plot. Only surfaces that are covered by a roof and enclosed on at least three sides count towards the ratio.

Can I exceed the land coverage ratio limit in Cannes zone UB with a permit?

Exceeding the limit is generally not permitted unless you qualify for a specific derogation, such as for public interest projects or architectural heritage reasons. In most cases, you must comply with the ratio, but you can consult the local urbanism department to explore possible exceptions.

📅 Mis à jour le 19/09/2026 — Cassini Expertise, expert bâtiment indépendant (06·83·13·40).