Does your home make the grade?

The HERS rating grades homes’ energy efficiency level

Posted on Oct 02 2019 in Energy

By Brian Hawk


Many first-time homebuyers are enthralled with their new purchase for many reasons. Some are excited to learn that their new house may be more energy efficient than their previous residence. The question is: how efficient? 

Fortunately, the nonprofit Residential Network Energy Services (otherwise known as RESNET) created a nationally recognized standard to determine the energy efficiency level of all homes. The Home Energy Rating System (HERS) Index calculates your home’s energy use and provides a relative performance score. Lower scores mean lower energy use – and a more energy efficient home! 

To calculate your home’s HERS Index score, a certified rater performs an assessment on your home and compares the data to a designed-reference home of the same size and shape. A HERS assessment includes collecting information about the home’s exterior walls, heating and cooling systems, windows, doors, attics, foundations, and air leaks. This is done during a visit to the home and typically takes two to four hours. RESNET explains that a home with a HERS Index score of 70 means the home is 30 percent more energy efficient than the reference home; a HERS Index of 130 would mean that the home is 30 percent less energy efficient than the reference home.

HERS Index scores are incredibly useful. A HERS rating can help differentiate a home you are selling, documenting how efficient it is. Energy efficient homes are often more attractive (and can likely get a higher price). If you are buying a home, a HERS assessment can provide details about areas of concern to identify what parts of the home should be improved if you do purchase the home. More information about the HERS Index is available at

Your local electric co-op’s energy advisor can help answer your questions about determining your home’s energy efficiency with an energy audit. While not the same as a HERS assessment, an energy audit will provide an in-depth analysis of your home to provide actionable steps you can take to make your home more energy efficient. Contact your local electric cooperative to learn how you can make sure that your home passes the energy efficiency test!

BRIAN HAWK is the energy advisor at Noble REMC in Albion, Indiana.