Get an idea of the effect of heat radiation yourself:
The thawing of 600g of ice, frozen at -18ºC, was tested inside two identical chambers and under the open sky.
Beginning 26.6. End 27.6.2019.
Measuring chamber 1 is covered with 3cm temperature insulation LPT-17.
Measuring chamber 2 is covered with 20cm mineral wool
After a 24-hour daytime rhythm, the direct comparison between the thick insulation and the thin temperature insulation, by the melt water, became measurable.
For the recording of the temperature curves one data logger per measuring chamber was inserted.
Under the 3cm thin temperature insulation only 290g of ice have melted to water, under the 20cm thick mineral wool, however, 380g of ice have melted to water.
For the temperature barrier, LPT-17, the heat flow into the measuring chamber was therefore only 3 W / h, but for mineral wool it was 4 W / h.
Due to the HEAT REFLEXANTS Lu..po.Therm therefore ~ 25% less heat energy penetrates into the measuring chamber, than with the clearly thicker mineral wool insulation!