Home Energy Rating System (HERS)

Comparing Apples to Apples with Energy-Efficiency

The description “energy-efficient” is not a government regulated term.  It may be used by any home builder who incorporates even the least energy-efficient products on the market into their homes.  So how does a consumer compare one home to another in the area of energy-efficiency?  How does he or she know that one home’s energy-efficiency is equivalent to that of another home?  There are many factors that contribute to a home’s energy-efficiency.  It is in looking at the home as a whole, a combination of its individual, energy-saving components, that one determines the true comparative-worthy value of the home.

HERS, or Home Energy Rating System, is a numerical index which represents the energy-efficiency of a home as a number.  (See Figure A.) 

HERS is based on whole house energy use. This rating system is consistent throughout the country and is similar in application to the miles per gallon rating system for cars.  It allows consumers to compare a product based on an evaluation standard (like comparing apples to apples).  On the HERS index, the lower the number is on the chart, the more energy-efficient the home.   

As you can see on Figure A, a standard home meeting building codes for minimum energy-efficiency achieves a rating of 100. An ENERGY STAR®-qualified home, built to exceed the minimum building codes and improve energy- efficiency by certain minimum standards, achieves a rating of 85.  Homes which incorporate additional energy-efficient designs and improvements achieve a rating of lower than 85.  Each point on the HERS index represents 1% of energy.  Therefore, ENERGY STAR®-qualified homes offer a 15% decrease in energy costs over the standard home with a 100 rating.  Our homes here at On Top of the World offer an energy cost savings of 15% – 35%...and we are improving upon this amount each year.

Visiting other communities? Ask them what their HERS rating is.