Thermal Imaging for Building Envelope Investigation

Thermal imaging (thermography) is a powerful diagnostic tool that reveals what the eye cannot see — temperature differences across building surfaces that indicate hidden defects.

How It Works

A thermal camera detects infrared radiation emitted by surfaces and converts it into a visual image showing temperature variations. Warmer areas appear in different colours to cooler areas, making anomalies visible.

What Thermal Imaging Can Reveal

Missing or Wet Insulation

Wet insulation conducts heat differently to dry insulation. Thermal imaging can identify moisture-saturated insulation without opening up the roof or wall.

Thermal Bridging

Cold bridges at junctions, lintels and structural connections show clearly as cooler patterns on a thermal image.

Air Leakage

Under pressurisation or depressurisation, air leakage paths become visible as streaks or plumes on the thermal image.

Hidden Defects

Voids behind render, delamination of external wall insulation and concealed construction defects can all be detected.

Limitations

Thermal imaging is not a standalone solution. It requires:

• A sufficient temperature difference between inside and outside (typically 10°C+)
• Dry conditions (rain affects surface temperatures)
• Correct interpretation by someone who understands building physics

When to Use It

Thermal imaging is most effective as part of a broader investigation — combined with moisture mapping, visual inspection and building physics analysis — rather than as an isolated test.