Relative Heat Gain

The amount of heat gain through a glass product taking into consideration the effects of solar heat gain (shading coefficient) and conductive heat gain (U-value). The value is expressed in Btu/hr/ft² (W/m²).

The relative heat gain is calculated as RHG = (Summer U-value x 14°F) + (Shading Coefficient x 200). The lower the relative heat gain, the more the glass product restricts heat gain.

Close this window.