What is a HERS Index Score, and how does it affect me?

HERS is short of Home Energy Rating System and is a process of evaluating the energy efficiency of a home. Without it, it’s just a guess on whether of not a home will perform well or cost you money. To earn a HERS Index score, there are many mandatory standards the home needs to comply with, such as window sealing, insulation, and wall sealants.

An independent certifier will first evaluate the house plans and provide feedback along with an estimated HERS Index Score. The certifier physically inspects the house at least twice. The first visit is when the insulation is being installed to ensure it is being done properly. The second visit is when the home is complete. At this point, the certifier makes a general visual observation, and then tests a home for “tightness” by performing a blower door test. A blower pressurized the home and a test meter measures how well the home hold the pressure. The lower the score, the better, just like the HERS Index Score. A typical new construction home is estimated to score at 100. A HERS Index Score of 50 would indicate that the home is 50% more energy efficient that a typical new construciton home.