🔴 Hot Spots
Red, Orange and Yellow colours indicate hot spots.
Building Thermography: How We Detect Invisible Insulation Problems
Imagine you had X-ray glasses that, instead of seeing bones, could see heat and cold. This is exactly what a Thermal Camera (or Infrared Camera) does.
Every object in the universe with a temperature above absolute zero emits infrared radiation (IR). The human eye cannot see this radiation. The thermal camera, however, reads this invisible energy and converts it into a colourful image on its screen, called a Thermogram.
1. How Do We Read the Colours?
In the most common colour palette used by engineers:
🔵 Cold Spots
Blue, Purple and Black colours indicate cold spots.
🏠 What We Want to See
If you stand outside your home on a cold winter night and look at it with the thermal camera, ideally you want to see it entirely blue (meaning the external surface is cold, so the heat has stayed trapped inside). If instead you see your wall "glowing" with bright red or yellow, it means your home is haemorrhaging energy to the street!
2. What Does the Thermal Camera Reveal? (The 3 Invisible Crimes)
Thermography is the ultimate "autopsy" for the energy condition of a building. It shows us with surgical precision problems hidden under tiles or behind plaster:
1️⃣ Thermal Bridges
Looking at the wall from inside (in winter), you see a perfectly painted surface. The thermal camera, however, shows you a huge, dark blue vertical stripe. This is the concrete column (the structural frame) that was never insulated and channels the freezing cold of the street directly into your living room.
2️⃣ Missing Insulation
You look at the ceiling (below the terrace) and see a blue "stain" in a square shape. Right there, beneath the slab, a piece of extruded polystyrene (XPS) is missing - the contractor forgot to install it or cut it crookedly.
3️⃣ Air Leaks (+ Blower Door)
When the home is under negative pressure, the camera "sees" the freezing air sneaking in. On the screen, it looks like a blue "river" that springs up from under the door or through a socket and flows across the warm (orange) floor!
3. The 10x10 Model Experiment (Buying a Renovated Apartment)
We find a 1990s apartment being sold as "fully and luxuriously renovated". We walk in: everything sparkles, the walls are pure white and smooth.
❌ Scenario A (Buying with the Naked Eye)
We are impressed by the new tiles, we buy the home at a high price. The first winter, the radiators run non-stop, we freeze and the ceiling corners fill with black mould. The "renovator" simply painted the walls and did not add a single centimetre of insulation.
✅ Scenario B (The Thermal Camera Inspection)
Before signing, we bring an engineer with a thermal camera. It is winter, we turn on the heating. The engineer scans the walls. The camera reveals a "skeleton" of dark blue lines (the frozen columns and beams) and enormous heat losses around the new windows. We immediately understand that the "energy upgrade" was a fraud. We save our money!
The Final Conclusion: Don't guess where your home leaks. Don't start demolishing walls searching for the problem. Thermography is a non-destructive, fast and absolutely precise method that shows you exactly where the building "hurts", so you can direct your investment precisely where it is needed.
Related Articles
Diagnosing moisture and mould with infrared camera Detecting insulation defects with thermal camera Blower Door Test: How it measures the 'holes' in your home When is the ideal season for building thermography
Ventilation, Airtightness & Real Consumption: Climate Control
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