Stepped Cracks: The Property Manager Calls Them « Cosmetic » and Blocks the Cat-Nat Claim
You’ve noticed stepped cracks on the corners and wings of your building following a period of drought. The property manager (syndic) calls them « cosmetic ». But a legal reality applies here: these cracks fall under the natural disaster insurance scheme (cat-nat), and the syndic has a legal obligation to file the claim within 30 days of the interministerial order officially recognising the natural disaster.

What’s at stake? Without this declaration, your condominium loses all right to compensation. And the syndic’s silence should not leave you without recourse.
The RGA Signature: Stepped Cracks on Corners and Wings
How to Recognise Clay Shrink-Swell Cracks
Cracks caused by clay shrink-swell subsidence (RGA) display a characteristic pattern:
- Stepped in shape: they follow the mortar joints rather than cutting through the bricks or stones
- Located on the building’s corners and wings: areas most exposed to moisture variation
- Vertical or semi-horizontal progression: a distinctive pattern of ground movement
These cracks are never merely « cosmetic ». They reveal structural ground movement beneath the foundations, classified as a natural disaster.
Duty of Care and Cat-Nat Declaration: The Legal Framework
Article 9 of the 1965 Condominium Act: The Syndic’s Unavoidable Duty
French condominium law (Loi 65-557) requires the syndic to safeguard the co-owners’ shared rights. In practice, this means:
- The syndic must declare any cat-nat event that could give rise to a compensation claim
- This declaration must be made within 30 days of the interministerial order recognising the natural disaster being published
- Missing this deadline means the condominium forfeits its right to compensation
What the French Insurance Code Says
Multi-risk building insurance policies do cover natural disasters. But this cover only applies if:
- The cat-nat order has been published
- The claim is registered with the insurer within the legal deadline
Once this deadline passes, the claim is permanently closed as far as your insurer is concerned.
The Syndic Delays or Refuses: Your Options
Formal Notice and Instructing the General Assembly
If the syndic refuses or keeps postponing the declaration:
- Send a formal notice (registered letter with acknowledgement of receipt) to the syndic, citing Article 9 of Law 65-557 and the 30-day deadline
- Call an extraordinary general meeting to instruct the syndic to act, or to replace them, in accordance with Article L.711-1 of the French Monetary and Financial Code
- Hold the syndic civilly liable: if the condominium suffers a loss (forfeited compensation), co-owners can take legal action against the syndic for breach of duty
How Cassini Settles the Matter: Expertise and Decisive Instruments
Crack Gauges: Measuring Progression Over Time
We install crack gauges on every significant crack. These precision micrometers record:
- The exact width at the date of installation
- Millimetre-by-millimetre progression across successive readings
- Whether the damage is accelerating or stabilising
Dated, signed readings: every measurement is documented and time-stamped, providing the material evidence accepted by insurers and courts.
Façade-by-Façade Mapping: The Foundation of Your Compensation File
We map every crack:
- Dimensioned façade plans for north, south, east and west, with precise locations
- Classification by severity (fine, medium, wide)
- Geolocated before/after photos throughout the survey
- An evolution chart correlating the cracks with drought events and moisture cycles
This mapping is the foundation of your compensation file. It proves to both the condominium association and the insurer that the damage genuinely originates from clay shrink-swell subsidence, fully justifying the cat-nat declaration.
FAQ: Your Questions Answered
Can the cat-nat claim be filed after the 30-day deadline?
Legally, no. The 30-day deadline is mandatory. After that, the claim is time-barred as far as the insurer is concerned. Case-law exceptions do exist (insurer deception, bad faith on the part of the syndic), but they are extremely rare and require going to court.
If the syndic refuses to file the claim, am I covered individually?
An individual co-owner’s home insurance never covers damage affecting shared structures (walls, foundations). Only a cat-nat declaration filed at the condominium level opens the right to compensation. This is exactly why taking action against a defaulting syndic matters.
How long does it take for RGA cracks to stabilise?
A full cycle takes at least 3 to 5 years: a dry spell causes the soil to shrink, a wet spell causes it to swell again. This is why the expert installs crack gauges to document the cycle. If nothing moves after 18 months, that’s a good sign.
What budget should I plan for repairing stepped cracks?
It depends on their extent. A cosmetic render costs little. But if the cracks go right through the façade (risking water infiltration), the masonry must be redone, joints resealed, and waterproofing reviewed: €3,000 to €15,000 per façade, depending on scale. This is exactly why cat-nat insurance matters so much: it covers these structural repairs.
Next Steps: Alert Your Syndic, Bring in an Expert
Have you spotted these cracks? Don’t wait. As soon as you notice them, write to the syndic by registered letter to report the damage and demand an immediate cat-nat declaration. At the same time, bring in an expert to install crack gauges and map the damage. Cassini documents your claim with the rigour insurers demand, turning simple « cracks » into a rock-solid compensation file.
Areas covered: the Côte d’Azur (06) and Var (83). Contact Cassini Expertise: 04 22 46 06 04 | [email protected]. We offer an on-site diagnosis and an action plan tailored to your condominium.
You Might Also Like
- Mould After a Flood: Who to Call
- Bathroom Humidity: Who Is Responsible
- Building Expertise in Antibes
Cassini Expertise
Expert du bâtiment indépendant — Antibes (06·83·13·40)
📅 Mis à jour le 25/09/2026 — Cassini Expertise, expert bâtiment indépendant (06·83·13·40).