Water Infiltration: Diagnosis, Expert Assessment and Solutions in the Alpes-Maritimes and Var

Water infiltration: a frequent and costly pathology in PACA

In the Alpes-Maritimes and the Var, water infiltration is one of the most common pathologies encountered in buildings, whether in co-ownerships or individual homes. Whether from rising damp, roof leaks, infiltration through façades, or underground networks, these defects cause structural damage, health issues (mould, allergies) and a significant loss of property value.

Types of infiltration and their causes

An accurate diagnosis of the infiltration is essential to determine its origin and establish liability. The main types of infiltration include:

• Infiltration through roofs and terraces: Waterproofing leaks, failed seals, standing water on flat roofs. Signs: stains on ceilings, peeling paint, musty odours.
• Rising damp: Moisture rising from the ground through walls by capillary action, particularly common in older buildings without a damp-proof barrier. Signs: salt efflorescence, peeling wall coverings.
• Infiltration through façades: Defective sealing of exterior joinery, cracks, porous joints. Signs: damp façades, deteriorating render.
• Infiltration from underground networks: Leaks in drainage or water supply pipes, often hidden. Signs: odours, abnormal vegetation growth, ground subsidence.

Technical diagnosis of infiltration

An amicable expert assessment of infiltration combines visual, instrumental and, where necessary, destructive investigation. The building expert will carry out:

• Visual inspection: Checking for signs of dampness, mould, and deterioration.
• Hygrometric measurements: Moisture levels in materials (plaster, wood, concrete) to quantify the extent of the damage.
• Thermal imaging camera: Revealing damp areas not visible to the eye (behind wall coverings).
• Watertightness tests: Water or smoke tests to locate leaks.
• Core sampling: Taking samples for analysis (material composition, moisture content).

Liability in cases of infiltration

Establishing liability is a key issue in an amicable expert assessment. Depending on the origin of the infiltration, different parties may be held responsible:

• Builder: 10-year statutory warranty (garantie décennale) for hidden defects affecting the structure’s soundness or making the building unfit for its purpose (roof leaks, defective waterproofing).
• Architect: 10-year contractual liability for design faults (poorly designed waterproofing systems).
• Owner: Routine maintenance (cleaning gutters, checking seals) and the 1-year completion warranty (garantie de parfait achèvement) for minor defects.
• Neighbour: Leak originating from a neighbouring property (civil liability).

Technical solutions and repairs

The amicable expert report proposes solutions tailored to each type of infiltration:

• Roof infiltration: Redoing the waterproofing, replacing membranes, improving slopes and drainage.
• Rising damp: Injection of water-repellent resins, installation of damp-proof barriers, perimeter drainage.
• Façade infiltration: Repointing, application of water-repellent render, replacement of exterior joinery.
• Underground networks: Repair or replacement of pipework, checking compliance with GTR standards.

Specific factors for infiltration in PACA

The Mediterranean climate and geological characteristics of the Alpes-Maritimes and the Var call for particular precautions:

• Mediterranean rainfall: Intense rain events (Cévenol-type episodes) that can overwhelm drainage systems and cause temporary infiltration.
• Shrink-swell clay soils: Differential ground movement that can crack pipework and foundations.
• Ageing housing stock: Many older buildings (pre-1980) built without seismic design or thermal insulation, making them more vulnerable.

Frequently asked questions about infiltration

How much does an amicable expert assessment for infiltration cost?
The cost varies depending on the complexity of the building and the scope of investigation required: from €1,200 to €3,500.

What are the time limits for taking action in the event of infiltration?
10-year statutory warranty (garantie décennale): 10 years from handover of the building. Completion warranty (garantie de parfait achèvement): 1 year. Direct action against the insurer: possible, subject to a 60-day notice period.

If infiltration is discovered several years later, does it still fall under the 10-year statutory warranty?
Yes, as long as it affects the soundness of the building or renders it unfit for its purpose, even if it appears several years after handover.

For infiltration issues in PACA, our amicable expert assessment can help you determine the causes, establish liability, and obtain compensation. Cassini Expertise covers the whole of the Alpes-Maritimes (06) and Var (83) departments.

Related articles

• Structural cracks vs. surface cracks: diagnosis and expert assessment in PACA

📅 Updated on 05/08/2026 — By Cassini Expertise, independent building expert covering the 06 & 83 departments. Free quote: 04 22 46 06 04.

📅 Mis à jour le 25/09/2026 — Cassini Expertise, expert bâtiment indépendant (06·83·13·40).