What You Need to Know About Solar Heat Gain Coefficient

The National Fenestration Rating Council tests and labels windows, skylights, and doors based on their energy performance. One way to measure a product’s energy properties is through its solar heat gain coefficient. In this article, a window and siding replacement company reveal what you need to know about SHGC.

What Is the Solar Heat Gain Coefficient?

Solar heat gain coefficient is the measurement of solar radiation admitted through a window, door, or skylight and released as heat into the interior space. Solar gain can enter a home in two ways:

• “Direct” solar radiation from the sun.

• “Absorbed” solar radiation is transferred through the glazing and framing materials.

How Is Solar Heat Gain Coefficient Measured?

Solar heat gain coefficient is expressed as a number between 1 and 0. The lower the SHGC, the less heat it transmits and the greater its shading ability. If you need a window, door, or skylight to collect solar heat during the cold, frosty winter, a product with a high SHGC rating will be more effective. Meanwhile, a product with a low rating is more likely to reduce cooling loads in the scorching summer months.

According to a window and siding installation specialist, the optimal SHGC rating for a particular window, door, or skylight will be determined by the local climate, orientation of the product, and external shading, such as trees, buildings and blinds.

How Do You Control Solar Heat Gain?

Many window and glass manufacturers regulate the intended solar heat gain or heat loss through tints, films, or coatings. There are also various levels of these coverings that can be applied to the glass in order to achieve the desired comfort level inside the home.

Hunterdon Roofing, Siding and Window Company is a premier source of exterior improvement solutions in Lebanon, NJ. Whether you need to replace your old, dingy windows or install new siding, our skilled team has got you covered! Give us a call at (908) 503-5393 or fill out our contact form to set up an appointment.