Radiant glass material configuration

Hello everyone

I am starting to learn about analysis in grasshopper with honeybee and I have a doubt, I started my simulation based on the one available on the ladybug page with the lighting analysis, but I have doubts about the configuration of Radiance Glass Material, it refers to transmittance in R, G and B, but how does this translate to U Value of the window? o Transmittance? Or does it simply refer to color, and if so, should I assemble the material with these characteristics?

simple glass

void glass glass
0
0
3 .96 .96 .96

Thank you!!!

I leave the model for review or if they find some kind of error.

Green Tower Oficina X01 ILUMINACION.3dm (95.7 KB) Green Tower Oficina X01 ILUMINACION.gh (568.0 KB)

It doesn’t! This material is only for daylight simulation. See the components for energy simulation for energy simulation materials and construction for glass.

See the averaged transmittance output value.

@Sebastian

There’s a really, really small, indirect relationship between transmittance and U-value that I’ll bring up as a point of interest (but I think you can effectively ignore in any practical application):

Your visible light transmittance will be slightly reduced if you apply a strong low-e coating to your window, which in turn can impact your glass thermal transmittance.

Of course, low-e coatings are designed to be spectrally selective, that is, designed to reduce transmission at the IR wavelength but not the visible light wavelength, so the impact is small, which is why you can ignore it in practise:

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