TECHNICAL-LEGAL EXPERT REPORT TEMPLATE – Judicial Expert in Construction

(Art. 335.1 LEC – Official Judicial Expertise)
Record:[Procedure number / Internal reference]
Inspection dateon-site:[dd/mm/yyyy]
Report issue date:[dd/mm/yyyy]
Appointed/party expert:[Name, ID, member number if applicable]
Name of expert: Aurelio Tamarit Blay
DNI:[XXXXXXXX-X]
Member no.:[Ex. No. COAAT-XXXXX / not mandatory for party experts]
Accredited qualification:Technical Engineer of Public Works (ETS of Civil Engineers, Canals and Ports).
Specialty: Judicial Expertise in Construction, Real Estate and Naval.
Contact:clients@aureliotamarit.es | +34 662 221 582
Professional address:[Address in Valencia, with RGPD applied]

🔹 I. BACKGROUND AND PURPOSE OF THE REPORT

In compliance with the order made by[Name of client / Lawyer / Court], and in accordance with the provisions of articles 335 et seq. of the Civil Procedure Law, this document is issuedindependent technical expert report, in order to:

Diagnose the origin and mechanism of the humidity observed in the single-family home located in [anonymized address: “residential area, Benidorm, Alicante”],
determine if its cause is attributable to construction defects, lack of maintenance or external factors,
and evaluate compliance with current technical regulations (CTE, EHE-08, ITC-01).

🔹 II. METHODOLOGY USED

A protocol has been followed based on:

• Visual inspectionon-site(day [date], time [time], weather conditions: [raining / dry / 48h without rain])
• Measurement with calibrated equipment (annual certificates, no. [XXX]):
• FLIR E8-XT thermocamera (resolution 320×240, precision ±2 °C)
• Gann GMH 3810 Resistance Hygrometer (range 0–100% RH, accuracy ±2%)
• HD industrial rigid endoscope with recording (Ø 6 mm, length 1 m)
• Document analysis: basic distribution plans (provided by property), deed of new construction (if applicable), repair history.
• Applied regulations:
• CTE DB-HS 3: Protection against humidity
• EHE-08, art. 32.4: Durability in elements exposed to environmental agents
• ITC-01 of the CTE: Pathologies due to differential movements
• UNE-EN 13183-1:2002: Moisture measurement in wood and porous materials
• RD 235/2013: Energy Efficiency Certificate (relation to pathologies)

🔹 III. PROVEN FACTSON SITE

✅Preliminary conclusion: The water does not come from the roof or from installations, but ratherpenetrates through the deficient crown and travels horizontally within the wall, filtering into the forging by capillarity.

🔹 IV. TECHNICAL ANALYSIS-FORGENSE

A. Failure mechanism

1. Phase 1 – Entry: Rainwater penetrates through cracks in the crown (absence of elastic joint).
2. Phase 2 – Transportation: The water descends by capillarity in the core of the double sheet wall (absence of water-repellent barrier → violationCTE DB-HS 3.2).
3. Phase 3 – Lateral diffusion: Upon reaching the slab (critical construction node), the water spreads horizontally across the plaster-slab interface.
4. Phase 4 – Manifestation: Visible leaks in ceiling + stains on vertical wall → symptomsnon-gravitational descenders.

B. Technical responsibility (according to jurisprudential doctrine)

• STS 456/2022: “The mere existence of moisture does not imply liability, but it does when a construction defect is demonstrated that violates mandatory regulations”.
• In this case,three objective breaches converge:

1. Lack of water-repellent finish (CTE DB-HS 3)
2. Absence of moisture barrier on walls in contact with the ground/open air (EHE-08 Art. 32.4)
3. Cracks due to unforeseen movements (ITC-01)

→ Pre-existing cause of writingif the work is <10 years (ten-year term, art. 1,591 CC).

🔹 V. EXPERT CONCLUSIONS (Art. 340.2 LEC)

1. ✅The origin of the humidity is a serious construction deficiency in the party wall, not attributable to lack of reasonable use or maintenance by the owner.
2. ✅The filtration mechanism is validated by objective tests(thermography, hygrometry, endoscopy), documented and dated.
3. ✅The solution is through structural intervention, non-palliative: crown sealing, water-repellent injection and passive ventilation.
4. ✅The report meets the formal requirements of art. 340 LEC: signature, identification of the expert, methodology, proven facts and reasoned conclusions.

🔹 VI. INTERVENTION PROPOSAL (Optional – for mediation or execution)

Indicative estimated cost (without VAT): €3,800–4,500 (depending on accessibility).

Note: quote closed after detailed measurement.

🔹 VII. ATTACHED DOCUMENTATION (Annexes)

1. Annex 1: Georeferenced and dated photographs (12 images)
2. Annex 2: Infrared thermograms with temperature scale and legend
3. Annex 3: Hygrometry records (signed and with calibrated equipment number)
4. Annex 4: Video capture of the endoscope (min 1:45–3:20, critical zone)
5. Annex 5: Technical sketch of the pathology (1:50 scale, with dimensions and details)
6. Annex 6: Equipment calibration certificates (current)
7. Annex 7: Photocopy of the DNI and certification of the expert

🔹 VIII. DECLARATION OF IMPARTIALITY AND CONFIDENTIALITY

The undersigned declares under his/her responsibility that:

• He has no personal, professional or economic relationship with any of the parties involved.
• This report is issued withtechnical independence and objectivity, without external influence.
• The data processed complies with theGDPR (EU 2016/679) and the Organic Law 3/2018.
• The report is delivered underprofessional secret(art. 24 LEC and art. 540 LECrim if applicable).

🔹 IX. SIGNATURE OF THE EXPERT

“In [City], on [date], being [time] hours, I proceed to sign this expert report as a sign of agreement with its contents.”

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