The SHGC or Solar Heat Gain Coefficient is a measure of the amount of heat that can be gained through your windows at times of direct solar contact. The SHGC is important as during summer the SHGC can add large amounts of unwanted heat to your house. Equally in winter the SHGC can be utilised to provide cost and pollution free heat from the sun. The Solar heat gain is measure as a coefficient and indicates the amount of direct solar heat that will penetrate your house.
The SHGC is mainly affected by the glazing type. Products like tinted glass and applied films can help to reduce the SHGC. It is important that when selecting windows and doors the orientation, location and house design are all considered to achieve the best outcomes. In cooler climates it is often advantageous to have a higher SHGC and in hotter climates a lower SHGC is better.