Technical tests to accredit hidden defects

For an expert report to hidden defects to be solid, it is not enough to describe the defect: it is necessary to prove it with objective technical means. This article summarizes the most common tests used by the court expert depending on the type of good and the defect investigated.

Structured visual inspection

Every intervention begins with a methodical visual inspection, supported by technical photography and, when appropriate, video. The condition of the property, the exact location of the defects, their extent and the surrounding conditions are documented. This phase is essential because it fixes the evidence of the moment and prevents subsequent repairs from erasing relevant traces.

Humidity measurements

In cases of humidity, contact and needle hygrometers are used to determine the moisture content in different points and compare affected areas with healthy areas. Moisture profiles help distinguish between different origins:

• Capillarity, with humidity concentrated in the lower part of the wall.
• Filtration, with concentration in areas close to the focus.
• Condensation, with a more uniform distribution and linked to thermal bridges.

Infrared thermography

The thermal imaging camera can detect surface temperature differences that reveal leaks, pipe breaks, thermal bridges, insulation deficiencies and areas with humidity not visible to the naked eye. It is a non-destructive technique that is especially useful for locating the origin without the need for initial exploratory openings.

Specific exploratory openings and trials

When surface evidence is inconclusive, small exploratory openings may be performed to access the hidden installation, cladding support, or suspect structural member. These exploratory openings are carried out in a controlled and documented manner, and where appropriate they are coordinated with the owner and, if the matter is judicialized, with the parties.

Specific instruments depending on the case

• Electrical installations: ammeter clamp, insulation meter, ground and differential tester.
• Structural: crackmeters, cores, laser meters and digital levels to monitor cracks and deformations.
• Vehicles: OBD diagnosis, paint thickness meter, dynamic tests and coordination with workshops when disassembly is required.
• Acoustics and thermal: sound level meters and thermal imaging camera when investigating insulation deficiencies.

Complementary documentary analysis

Along with the physical evidence, the report usually incorporates documentary analysis: construction project, quality report, installation bulletins, certificates, vehicle maintenance history, MOT reports, communications with the seller and contracts. The confrontation between what was declared and what was technically detected reinforces the conclusion.

Chain of custody and traceability

Each sample, measurement and test is documented with date, time, exact location and equipment used. This traceability is essential if the report is provided in a judicial proceeding and ensures that the conclusions can be defended in court.

To know the next steps of an expert assignment, see the section Process or the specialty of Hidden defects. To speak with Pablo Gómez Thoren, registered court expert no. 846 (AEPEJU), go to Contact.