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Hello,

I am working on a project in Southern California (cooling-driven climate) in which annual energy usage increases when the SHGC is lowered from 0.27 to 0.25. This is noticed when window properties are input with the "SimpleGlazingSystem" method.

The different curves utilized to estimate angular transmission properties for SHGC change according to input. This causes a slight increase in cooling energy when SHGC is in the range of (0.250 - 0.269).

By inputting 0.249 in models that have 0.25 SHGC, the resulting energy usage is in line with what would be expected. My question is if anyone has identified a work around if the window is 0.26 SHGC. Unfortunately is has to be a work around that can be made with the SimpleGlazingSystem approach as I am modeling through CBECC-Com, which currently only supports the simple approach.

Thanks!

Hello,

I am working on a project in Southern California (cooling-driven climate) in which annual energy usage increases when the SHGC is lowered from 0.27 to 0.25. This is noticed when window properties are input with the "SimpleGlazingSystem" method.

The different curves utilized to estimate angular transmission properties for SHGC change according to input. This causes a slight increase in cooling energy when SHGC is in the range of (0.250 - 0.269).

By inputting 0.249 in models that have 0.25 SHGC, the resulting energy usage is in line with what would be expected. My question is if anyone has identified a work around if the window is 0.26 SHGC. Unfortunately is has to be a work around that can be made with the SimpleGlazingSystem approach as I am modeling through CBECC-Com, which currently only supports the simple approach.

Thanks!