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Old 07-27-2018, 07:49 PM   #37 (permalink)
Vman455
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I'm dragging this thread back up because I just removed my antenna and now have a nice, smooth roof to wrap with something more reflective than the silver paint.

I need to decide between white vinyl or chrome vinyl. The above posts about emissivity vs. reflectivity make some good points, but no one has mentioned the fact that emissivity and reflectivity sum to 1 for any given wavelength. So, in the spectrum where that paint has an emissivity of .90-.95, it has an abysmal reflectivity of .05-.10. Add to that that we're talking about the same material in two different colors, not paint vs. metal, and I'm not sure having a good emissivity rating in any particular part of the spectrum is as important. Plus, there will be silver paint underneath, which has a fairly balanced .57 reflectivity/.43 emissivity in visible spectrum.

As near as I can tell, even at sea level the bulk of solar radiation is in a visible spectrum, not IR, where chrome should outperform white. Has anyone else experimented with these wraps? Which should I go with?
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