What is the HERS Index?

From LED light bulbs and solar panels to low-flow shower heads and whole house fans to make your HVAC cooling more efficient, there are many ways to decrease your consumption of energy. Often, the first step to identifying cost-effective fixes is a HERS score.

What Is the HERS Index?
The HERS Index, which stands for Home Rating Energy System, is how the energy efficiency of a home is measured. The HERS Index is a trusted measurement of the energy performance of a home.

 It's the industry standard way of measuring a home's energy efficiency developed by RESNET (Residential Energy Services Network), a non-profit organization accredited by the American National Energy Standards Institute (ANSI) as a Standard Development Organization.  It's additionally a nationally recognized system used to inspect and calculate the energy performance of a home.

What Are the Benefits of HERS-Rated Homes?
A HERS Rated home is good for your family's comfort and health, the environment, and your finances.

Benefits include:

  1. Energy efficient homes could help save you between 5% to 30% on your energy bills, according to the DOE.
  2. A HERS rated home is built using a fresh air ventilation system that ensures you're continuously breathing fresh air in your house, which contributes to a healthier lifestyle.
  3. A HERS rated home provides better energy performance and is better insulated and better built, which makes it cooler in the summer and warmer in the winter.
  4. Having the confidence your house has been tested and inspected by a certified, trained and independent HERS rater and meets national energy standards can give you peace of mind.
  5. In 2018, homes that were energy efficient sold 89 days quicker than traditional homes.

How Does the HERS Index Work?
You would have a certified Home Energy Rater come in and evaluate your home's energy efficiency and assign the HERS Index Score (a relative performance score). The lower the score, the more energy efficient your home is. A typical resale home will score 130 on the HERS Index, according to the U.S. Department of Energy, while a 2006 International Energy Conservation Code built home receives a rating of 100.

To calculate the HERS Index Score of your home, a certified HERS Rater will come in and perform an energy rating and then compare the data with a designed model home (reference home) of the same shape and size as your actual home. Therefore, your score will always be relative to the shape, size, and type of home you live in. A home with a 70 HERS Index Score is 30% more energy efficient than a RESNET Reference Home. One that has a 130 HERS Index Score is 30% less energy efficient.

More than one million homes in the U.S. have an issued HERS Index Score in the US.