SRI

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Is there a place to enter the solar reflectance index (SRI) for the roof
material?

I have looked in detailed mode in the materials properties, but no luck.

Maybe it is called something different in equest?

Thanks,

Timothy W. Hill

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Hi Tim,

Someone else can correct me if I'm wrong, but I believe that you can input
1 minus your SRI to get the solar radiation absorptance of your
construction. This is an input in the "Construction" heirarchy of detailed
mode -- I believe eQuest lists it as "Ext. Color (absorpt.)".

*Michael Hsueh*

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Both reflectance and emittance are included in the SRI. If you don't have these values, but have the SRI, one way to back them out is by using this calculator:
http://coolcolors.lbl.gov/assets/docs/SRI%20Calculator/SRI-calc10.xls
You will have to enable macros to use the workbook.

Absorptance (= 1 - reflectance) is entered for the Construction, while emittance/emissivity is a property of the exterior Surface.

Regards,
Bill

[Senior Energy Engineer 28Jun2012]

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