Shading Coefficient VS G-Value 2

[Calador]

Hi,

I am not really sure whether this is the place to put this query into but here goes anyway.

I have a question regarding the difference between the shading coefficient and the G-value of the glass. I have looked into some documents and their interpretations vary quite significantly (in my view anyway). I basically want the basic definition of how you define each term.

Please shed some light on this matter. Thanks!

 

[BrunoPuntzJones]

Shading coefficient is an older term which is being replaced in the US with the Solar Heat Gain Coefficient (SHGC).

The Solar heat gain coefficient is the fraction of incident solar radiation that actually gets through a window as heat gain (transmitted radiation + absorbed and re-radiated energy). To convert a Shading Coefficent to SHGC, mutliply the SH by 1.15.

SHGC is the equivalent for the European G value. The only difference between the numbers is that SHGC uses an air mass of 1.5 and the g value uses an air mass of 1.0.