Solar heat gain coefficient (SHGC) refers to the amount of solar radiation that can pass through a window or skylight. Understanding the use of SHGC ratings can be beneficial to energy-conserving homeowners who are designing or renovating a home.

Keep reading to find out what SHGC ratings are ideal for your windows.

Why Do You Need to Use SHGC Ratings?

SHGC ratings are used to quantify the energy efficiency of a window assembly, which is the combination of glazing, framing and spacers. These ratings allow for a straightforward comparison of various window products.

It is important to know how a window or skylight reacts in relation to solar heat. For example, a window that allows a copious amount of solar heat to pass through is best utilized in climates where warmth from the sun is sought.

How Are SHGC Ratings Determined?

The National Fenestration Rating Council® (NFRC) assigns SHGC ratings. It is a non-profit organization that administers the independent labeling for the energy performance of windows, skylights and doors. SHGC ratings are stated on labels attached to the products. Also available on the label are the air leakage, condensation resistance, U-factor and visible transmittance ratings. All of these factors determine the overall energy performance of a product.

Ideal SHGC Ratings for Different Climates

A low SHGC is best used in cooling-dominated climates. Ideally, these regions should utilize skylights with an SHGC of less than 0.30 and windows with a rating of less than 0.27. In colder climates where air conditioning is generally not a concern, an SHGC rating between 0.30 and 0.60 is advised. In mixed climates where both heating and cooling are used, but with less emphasis on cooling, an SHGC of less than 0.40 is best.

Exterior Building Solutions specializes in a wide range of exterior improvements, including installing energy-efficient doors and windows. Give us a call at (314) 470-8783, or fill out our convenient online form to request a quote.