 Reference Home (based on the 2006 International Energy Conservation Code) scores a HERS Index of 100, while a net zero energy home scores a HERS Index of 0.
Your HERS Score comes in handy in several places:
- Stand-alone score: By itself, it gives you a good idea of how your home compares to a baseline home. I’m a firm believer that when we have quantitative values to use for comparison we are able to better define how we need to improve. For instance, you can get a certified Home Energy Rater to analyze your home on date 1, then you can make the suggested improvement, and at date 2 you can get your home rated again to see how much your score has improved.
- LEED for Homes: If you want to get a LEED score for your home, like Lorraine and Judd Horalby who we covered in our post on LEED for Homes, then chances are it will utilize the HERS index to help determine what level of LEED status your home will achieve.
- Energy Star for Homes: Energy Star for Homes is different than Home Star (a.k.a. Cash for Caulkers bill) but is yet another energy efficient stamp of approval (just like LEED for Homes is). LEED for Homes is monitored by the U.S. Green Building Council (which actually is not a government program, it is a non-profit) while Energy Star for Homes is a joint project by the U.S. DOE and EPA. The EnergyStar website has a nice summary of the relationship between the HERS Index and Energy Star for Homes: “A home energy rating involves an analysis of a home’s construction plans and onsite inspections. Based on the home’s plans, the Home Energy Rater uses an energy efficiency software package to perform an energy analysis of the home’s design. This analysis yields a projected, pre-construction HERS Index. Upon completion of the plan review, the rater will work with the builder to identify the energy efficiency improvements needed to ensure the house will meet ENERGY STAR performance guidelines.”
As you can see, HERS and the HERS Index (Score) come in handy in several places (yes, I know it gets confusing sometimes). By giving home energy raters a set of standards to measure how efficient a home performs, HERS helps homeowners and homebuilders understand how efficient their home is and how they can improve.