Solar Heat Gain Part 1: Its Effects on Your Home

Shopping for windows can be overwhelming, especially for those doing it for the first time. Other than color, type, and materials, you will also need to choose an energy-efficient. Energy efficiency depends on solar heat gain capacity of a window glass. Solar heat is simply defined as the shortwave radiation from the sun as it heats the property through openings such as windows or fabrics.

Solar Heat Gain

What are the effects of solar heat gain?

As the solar heat gain increases, the temperature in the room also increases. When this happens, you will feel hot and you will have to open the windows to let cool air in. This is beneficial in areas with cooler climates, as this is usually considered a passive source of heat. In areas with a warm climate, however, this can be problematic. Heated objects radiate the heat, but it won’t be able to pass through the glazing of the glass outside. The result is an accumulation of heat in the interior space, also known as the greenhouse effect.

Although greenhouse effect is a natural process, it can have a negative impact on the environment. Excessive heat can cause an exponential increase in cooling bills on your property, for starters. It is imperative that homeowners are aware of these effects and the solutions before it gets worse.

With Renewal by Andersen® of Houston, we recommend the installation of an energy-efficient replacement window. Our selection includes traditional double hung, sliding, awning, and picture windows. Our windows are made with Fibrex® frame and Low-E4® glass. Compared to other types of glass, our Low-E4 glass is 45% more energy-efficient and up to 56% more in winter.

How do you measure your window’s SHGC?

Solar heat gain on windows is measured in terms of solar heat gain coefficient (SHGC). The rating is described as a ratio between 0 and 1, where 0 is least and the 1 is the maximum possible amount of heat that can pass through the window. Since 1993, the procedure for testing windows, doors, skylights, and other attachments is performed by the non-profit organization National Fenestration Rating Council (NFRC). Ratings and labels are administered by NFRC and these are taken into account by the Department of Energy and EPA when evaluating the energy efficiency of products for certification or rebates.

Still, note that energy efficiency ratings vary based on climate. For instance, if you are planning to install sliding windows and you live in the South where cooling is required, the SHGC of the window should be less than 0.27. For skylights, it should be less than 0.30. If you live in cooler northern regions, windows should have an SHGC rating of less than 0.40 during summer. For regions with a mixed, temperate climate, windows with SHGC rating of less than 0.30 will be beneficial, especially when cooling costs increases.

Call us today at (877) 533-6610 for your free estimate on energy-efficient windows. We serve Sugar Land, TX, and surrounding areas in Texas.