Primarily, one wants to make surface temperatures or temperature differences visible.
A well-insulated wall, for example, is almost at outdoor temperature; the window is naturally not as well insulated and therefore appears yellow or red.
This is done in winter, because you see no or hardly any temperature differences when it is 25 degrees outside.
Hi Peanuts74,
ah ok. Interesting.
What do you do then, or what conclusions do you draw when you have the temperature differences in front of you during nighttime/cold periods?
Example: Suppose I have a house made of natural stone. We are talking about a wall of it now. This wall has no window or anything!
This natural stone construction "insulates" the house according to the energy saving ordinance, without additional insulation.
This wall is then warm/red in the evening and cold/blue during the day.
What do I conclude from that?
For me, what you conclude always comes across like this:
"Ha! Outer wall is red/warm, so you are heating the street. In other words, add insulation!"
Even though everything is actually fine.
Thanks for your patience!