An infrared photo, also called a thermal image or thermography, is an image taken with an infrared camera that makes temperature differences on the surface of a building visible. Warm spots appear red/yellow, cold spots blue. In this way heat loss is literally made visible, without opening up the structure.
How does it work?
Every surface emits infrared radiation depending on its temperature. A thermographic camera measures this radiation and converts it into a colour image. Places where heat escapes outward — or where cold penetrates inward — therefore stand out immediately.
What does an infrared photo reveal?
- Thermal bridges — places where the insulation is interrupted, such as concrete edges, lintels and connections
- Insulation defects — missing or slumped insulation in cavity, roof or floor
- Air leaks — draughts along window frames, joints and penetrations
- Damp patches — moist material has a different temperature
- Pipe routing — underfloor heating and hot-water pipes show up
Application
- Energy survey — tracing heat loss before making a home more sustainable
- Check after insulating — verifying that cavity or roof insulation sits well everywhere
- Building inspection — moisture and leak detection
- Underfloor heating — locating pipes before you drill
Points to note
- Take images when there is a sufficient temperature difference between inside and outside (best during the heating season)
- Sun, wind and rain shortly before the measurement can distort the image
- A thermogram shows symptoms; the cause requires skilled interpretation
Related terms
- Insulation
- Thermal bridge
- Energy saving
- Air tightness
- Building moisture
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