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Tiled rooftops seen from above during a drone inspection

C-DRONE GUIDE · 31 JULY 2026

External insulation (ETICS) diagnosis in condos by drone thermography: price

External thermal insulation (ETICS) has become the reference way to renovate a building's envelope without losing floor area: the façade is clad with insulation covered by render or cladding. Well installed, it transforms the building's performance; badly installed, it creates thermal bridges, traps moisture and debonds. Yet ETICS defects are rarely visible to the naked eye from the street: they read in thermography, façade by façade, over the full height. For a condo board committing hundreds of thousands of euros of works, drone thermography is a handover and evidence tool. Here is what it detects, when to schedule it, and prices observed in 2026.

Published on 31 July 2026, reviewed on 31 July 2026 — regulations in force as of July 2026.

Why ETICS is checked with thermography

ETICS is a system: bonded and/or mechanically fixed insulation, reinforcement mesh, finishing render. Each link has its defects: missing insulation or open joints between boards, insufficient fixing, thermal bridges at window reveals, balconies and shutter boxes, debonding of the system from its substrate, and water ingress migrating behind the render. All change the surface-temperature map: an insulation gap lets heat from the heated dwelling through and draws a warmer zone seen from outside in winter.

Thermography can also reveal the system's hidden elements. A study by Simões, Simões, Serra and Tadeu presented in 2015 in Thermosense (SPIE) shows that active infrared thermography can locate even the mechanical fixings and internal defects of an external insulation system (see the study on Google Scholar). That is what makes the check so useful at handover: you verify not only the visible result but the quality of the installation beneath the render.

The drone: full height, façade by façade

On a five-storey building or taller, ground thermography struggles with shooting angle: upper floors are seen obliquely and poorly measured. The drone positions itself square to each floor, at constant distance, and delivers even coverage from base to top, paired with visible images to place each anomaly on the elevation. It is the same logic as our façade diagnosis before renovation guide, applied this time to the insulation system's thermal performance.

Measurement quality depends on acquisition rules — distance, angle, conditions — studied by Mayer and co-authors in 2023 in Remote Sensing for drone building thermography (see the study on Google Scholar). In practice: winter flights, early morning, an indoor/outdoor gap of at least 10°C, shaded façades to avoid parasitic solar radiation. For an occupied building, the job is prepared with the property manager (resident information, privacy handled as in our GDPR and professional drones guide).

Works handover and file evidence

The best time to thermograph ETICS is at handover, during the first heating season after the works: installation defects are still under warranty, and the dated thermographic report is solid evidence if a reservation is raised. It naturally feeds works acceptance by drone and, in a condominium, dovetails with the envelope thermography described in our collective EPC and works plan guide.

The second useful moment is after a problem: staining, render blistering, a cold-wall feeling in some flats. Thermography objectifies what occupants feel and directs the contractor to the zone to repair, rather than reopening the façade at random. In both cases the limit is clear: the drone provides the exhaustive, located survey; adversarial interpretation and qualification of the defect remain the project manager's or expert's job.

Prices observed in 2026

Ranges observed in 2026 (excl. VAT):

The window is winter and early-morning: book ahead. Our thermal imaging drone page presents the service; request a quote stating building height, finish type (render, cladding) and context (handover or defect).

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Put it into practice

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