Is complying with U-values mandatory in GRIHA?

Query

Can you please clarify on U value constraint of GRIHA? As we have clear glass on windows and few windows have large shading devices thus SHGC is below 0.25 but U value is 5.8 w/m²k. So should the glazing comply with both SHGC 0.25 and U value 3.3 w/m2k or only SHGC compliance?

Solution

Complying with the glass U value is not a mandatory requirement of GRIHA. However SHGC compliance is a mandatory clause in Criterion 13, GRIHA Version 3.