Infrared Thermography
Thermal Imaging for Subsurface Defect and Moisture Detection
Infrared thermography (IRT) detects subsurface defects and anomalies by measuring surface temperature variations caused by differences in thermal conductivity within a structure. Delaminations, voids, moisture ingress, and insulation defects all produce characteristic thermal signatures that are invisible to the naked eye but clearly visible in infrared imagery. TRSC uses IRT as a non-contact, wide-area screening technology that identifies zones requiring detailed physical investigation.
The technique works because subsurface defects alter the rate at which heat flows through a structural element. A delamination traps air, a thermal insulator, causing the surface above it to be warmer than surrounding intact areas during solar heating. Moisture-saturated zones have higher thermal mass and conductivity, causing them to appear cooler during drying phases. These temperature contrasts, often as small as 0.5°C, are detected by modern thermal cameras with millikelvin sensitivity.
IRT is particularly valuable for facade assessment, where large areas can be surveyed from ground level without scaffold or access equipment. A thermal survey of a building facade that would require days of scaffold-based visual inspection can be completed in hours, identifying the specific areas where detailed investigation or repair is warranted. This targeted approach significantly reduces overall investigation cost.
TRSC conducts IRT surveys under controlled thermal conditions, typically during the heating phase (morning sun on facades) or cooling phase (evening) when thermal gradients across defects are maximised. Survey timing is critical to result quality and is planned based on facade orientation, weather conditions, and the type of defect being investigated. All IRT surveys are conducted by thermography-trained engineers who understand both the thermal physics and the structural implications of the findings.
Speak with an RPEQ-qualified structural engineer about deploying this technology on your asset.
Applications
Facade Delamination Detection
Identifying tile, render, and cladding delamination across building facades from ground level, mapping areas at risk of falling debris without scaffold access.
Moisture Ingress Mapping
Detecting moisture migration paths through walls, roofs, and slabs by identifying thermal anomalies associated with wet zones and evaporative cooling.
Insulation Defect Identification
Locating missing, damaged, or displaced thermal insulation in building envelopes, identifying thermal bridging and energy loss pathways.
Electrical Fault Detection
Identifying overheating electrical connections, switchboards, and distribution boards through thermal anomaly detection before failure occurs.
Underfloor Heating Verification
Mapping active heating circuits and identifying blockages or non-functioning zones in hydronic and electric underfloor heating systems.
Post-Repair Verification
Verifying bond quality of facade repairs, waterproofing installations, and insulation replacement through thermal signature comparison with surrounding intact areas.
Frequently Asked Questions
Can IRT detect all structural defects?
No. IRT detects defects that produce thermal anomalies, delaminations, voids, moisture, and insulation gaps. It cannot detect reinforcement corrosion, concrete strength variation, or structural cracking that does not create a thermal pathway. TRSC uses IRT as a screening tool to identify areas for further investigation using GPR, UPV, core testing, or physical inspection.
What weather conditions are needed for IRT surveys?
IRT surveys require a temperature differential between the structure and its surroundings. Ideal conditions include clear skies, low wind (<15 km/h), and either solar heating or cooling phases. Rain, heavy cloud cover, or high wind speeds reduce thermal contrast and may prevent effective surveying. TRSC schedules IRT surveys for appropriate conditions and will reschedule if conditions are unsuitable.
How far away can IRT detect defects?
Detection distance depends on defect size, thermal contrast, and camera lens. With a telephoto lens, defects as small as 100mm can be detected at distances of 30–50m. Larger defects (facade delamination panels) can be detected at greater distances. TRSC selects lens and survey distance to match the investigation objective and the building geometry.
Deploy IRT on your asset
Every investigation begins with a direct conversation with an RPEQ-qualified structural engineer. No sales intermediary, contact TRSC to discuss whether infrared thermography is appropriate for your structural question.