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planning:thermal_protection:thermal_protection_works:insulation_increases_comfort_-_evidence_no.3_outdoor_thermography [2014/09/18 18:19] – external edit 127.0.0.1planning:thermal_protection:thermal_protection_works:insulation_increases_comfort_-_evidence_no.3_outdoor_thermography [2022/01/25 13:17] (current) ggrosskopf
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 These IR images are rather revealing: These IR images are rather revealing:
  
-  * ** The outdoor air temperature is approx. 6.46 °C ** as measured at the surface of the bags hanging from the scaffolding. The surfaces of these bas have reached a temperature equilibrium with the outdoor air; therefore they neither give off heat nor do they absorb heat.   +  * ** The outdoor air temperature is approx. 6.46 °C ** as measured at the surface of the bags hanging from the scaffolding. The surfaces of these bags have reached a temperature equilibrium with the outdoor air; therefore they neither give off heat nor do they absorb heat.    
   * ** The temperatures measured for the areas of the facade that have already been insulated are very uniform** and rather similar to that recorded for the bags – rendering the bags barely noticeable in the thermal image. Nevertheless, the insulated surface is slightly warmer than the surrounding objects. Since the thermal image was taken before sunrise, direct or indirect sunlight would not be the cause for the slightly higher temperatures of 6.81 °C on average.  In fact, the temperature difference is due to small heat losses which remain even with the wall being insulated. The uniform image in the area that has already been insulated is a good sign, showing that the insulation has been properly applied.   * ** The temperatures measured for the areas of the facade that have already been insulated are very uniform** and rather similar to that recorded for the bags – rendering the bags barely noticeable in the thermal image. Nevertheless, the insulated surface is slightly warmer than the surrounding objects. Since the thermal image was taken before sunrise, direct or indirect sunlight would not be the cause for the slightly higher temperatures of 6.81 °C on average.  In fact, the temperature difference is due to small heat losses which remain even with the wall being insulated. The uniform image in the area that has already been insulated is a good sign, showing that the insulation has been properly applied.
 +
    * ** The facade areas of the heated upper floor which have not yet been insulated have a much higher average temperature of 9.14 °C. Moreover, their temperatures are not uniform.** This is due to a number of reasons: In some areas, significant heat losses are caused by thermal bridges – e.g. at the edge of the window where the heat only travels a short distance the masonry. In other areas, furniture is positioned along the external walls serving as partial interior insulation and reducing the temperature in these areas.  Incidentally, the temperature of the interior wall surface behind the furniture is also lower – which may cause severe problems (see [[planning:thermal_protection:thermal_protection_works:insulation_prevents_structural_damage_evidence_no.4_measurements_in_a_retrofit#Problems due to moisture build-up|Problems due to moisture build-up]]). Therefore, furniture should not be placed directly next to poorly insulated exterior walls.      * ** The facade areas of the heated upper floor which have not yet been insulated have a much higher average temperature of 9.14 °C. Moreover, their temperatures are not uniform.** This is due to a number of reasons: In some areas, significant heat losses are caused by thermal bridges – e.g. at the edge of the window where the heat only travels a short distance the masonry. In other areas, furniture is positioned along the external walls serving as partial interior insulation and reducing the temperature in these areas.  Incidentally, the temperature of the interior wall surface behind the furniture is also lower – which may cause severe problems (see [[planning:thermal_protection:thermal_protection_works:insulation_prevents_structural_damage_evidence_no.4_measurements_in_a_retrofit#Problems due to moisture build-up|Problems due to moisture build-up]]). Therefore, furniture should not be placed directly next to poorly insulated exterior walls.  
 +
   * ** The heat emitted by an object is roughly proportional to the temperature difference between this object and the outdoor air temperature**. \\ In this case, the difference is:\\   * ** The heat emitted by an object is roughly proportional to the temperature difference between this object and the outdoor air temperature**. \\ In this case, the difference is:\\
 for the uninsulated wall: 9.14 – 6.46 = 2.68 degrees for the uninsulated wall: 9.14 – 6.46 = 2.68 degrees
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 \\ \\
  
-== Note on the tilted window ==+==== Note on the tilted window ====
  
 The following images illustrate the thermal effects around the tilted window in this building. They are both the same image, displaying different temperature ranges:  The following images illustrate the thermal effects around the tilted window in this building. They are both the same image, displaying different temperature ranges: 
   * The image on the left only shows temperatures between 2 and 10 degrees Celsius, higher temperatures are displayed as white areas.   * The image on the left only shows temperatures between 2 and 10 degrees Celsius, higher temperatures are displayed as white areas.
 +
   * The image on the right shows temperatures between 2 and 20 degrees Celsius revealing the tilted window as well as the window sill (light purple). The temperature at the interior surface is close to 19°C.     * The image on the right shows temperatures between 2 and 20 degrees Celsius revealing the tilted window as well as the window sill (light purple). The temperature at the interior surface is close to 19°C.  
 This example illustrates just how well the insulation works: Even with the window open, the interior surface of the wall stays warm even right next to the thermal bridge due to the window installation.\\ This example illustrates just how well the insulation works: Even with the window open, the interior surface of the wall stays warm even right next to the thermal bridge due to the window installation.\\
planning/thermal_protection/thermal_protection_works/insulation_increases_comfort_-_evidence_no.3_outdoor_thermography.1411057157.txt.gz · Last modified: 2014/09/18 18:19 by 127.0.0.1