How Can the Glass in Your Windows Help Cool Your Home?

Window glass can be an ally in the battle to keep your house cool during the summer. Or, it can be a major contributor to the problem. During hot weather, it’s estimated that standard single-pane windows are the greatest single contributor to solar heat gain (SHG), typically accounting for approximately 48% of the heat entering a home from outdoors. This energy, which is present in sunlight, streams through standard glass and accumulates indoors, raising temperatures as well as summer operating costs as your air conditioner runs longer cycles to keep up with the heat gain.

How Much Gain Is Too Much?

Solar heat gain through windows is measured by a coefficient (SHGC) between 0 and 1. The closer to 1 a window is rated, the more heat the glass will admit to the interior of the home. Ratings closest to 0 reject the most heat. The best choice for residential applications are Energy Star-certified windows tested and verified by the Environmental Protection Agency with an SHGC around 0.40 or less. This provides the best compromise of effective heat rejection during the summer while still admitting sufficient solar energy to augment heating during cold winter months.

Making Glass Efficient

Window glass that reduces heat gain falls into two basic categories:

  • Insulated windows are formed with two or more closely spaced panes of glass separated by a thin, insulating air space. More expensive insulated windows fill the air space between panes with inert, nontoxic gas — typically argon or krypton — which offers better insulating properties than air.
  • Low-e coated. Short for low emissivity, low-e windows have a thin, invisible layer of microscopic, metal-oxide coating that rejects solar heat while still admitting most visible light. Low-e coatings range from types designed to block moderate heat gain to those that block more substantial amounts. Depending on the type, low-e glass can reject 40% to 70% of incoming solar heat.

For more advice about upgrading to efficient window glass, contact the Paitson Bros. professionals. We’ve been keeping you cooler every summer since 1922.

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    By Jeff Paitson
  • About Jeff

    Jeff Paitson Jeff Paitson is a third generation business owner who continues to run the business with the same values that have been passed down from previous generations since 1922.

    Jeff’s belief is that the business belongs to Jesus Christ; therefore 10 percent of the company’s profits go toward the Maryland Community Church.

    Jeff is a Terre Haute Chamber of Commerce member and in his spare time, he enjoys photography.
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    Ethan Ethan Rayburn is a lifelong resident of Terre Haute and a 2005 graduate of Purdue University.

    An Eagle Scout, Ethan spent four years as a non-profit executive with the Boy Scouts of America before joining Paitson Bros. as a comfort advisor and later General Manager. In that role, Ethan has brought a renewed enthusiasm for customer care, integrity, value, and service to Paitson Bros. Heating & Air Conditioning.

    Ethan enjoys singing and was a member of the Purdue Varsity Glee Club. He also enjoys playing and coaching soccer, spending time with his family and two young boys, and volunteering his time and resources with his church, Terre Haute First Baptist Church, which he has attended from a very young age.
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