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Most people are comfortable with temperatures in a very small temperature band; between 22 – 26 degrees Celsius (thermal comfort zone). This leads to big energy expenditure to heat or cool spaces to fall within this range. In every day life, the answer seems to be simple. If it is cold; switch on a heater or switch on the air-conditioning when it is hot.

The question which is seldom asked is: what are we really heating and cooling and how does that effect our energy consumption and carbon footprint. Heat escaping (trying to heat the whole neighbourhood) or cold invading (trying to keep the neighbourhood out) is invisible to us. However, we do have help in finding out the truth.

Thermographic cameras can “see” and photograph the “real” state of affairs in terms of the heat loss or gain of buildings. Fig. 1, is of a highly energy efficient and well insulated house in Germany. The concept is called a Passivhaus. In the background is an average European house. Note how the average house as a higher heat emissions footprint than that of the Passivhaus. In other words, the Passivhaus needs less energy to keep constant comfortable environment for the people that live there.

The efficiency in warming or cooling is wholly dependant on the extent of the insulation of a building. This is especially true where fossil fuels are used to cool or heat the building.


There are many different areas of insulation that is important; some is logically, others are almost always over-looked. Here is a cursory list of areas that need to be insulated:

  • Roofing
  • Walls
  • Windows
  • Flooring
  • Doors

Fig.2, is an example of a poorly insulated house. It is clear that the people are paying not only to heat there house but also their neighbours. This image was taken in South Africa and represents the average house or building. In conclusion; insulation is not only for cooler climates but essential to every building, irrespective of the climate.