With home energy costs skyrocketing, it only makes sense to find out how energy efficient a home really is. The U.S. Department of Energy estimates that a home built to the 2004 International Energy Conservation Code uses 30% less energy than older homes. Many builders today are building homes that use 70% less energy than existing ones.

A home built to the 2004 International Energy Conservation Code is awarded a rating of 100 on the HERS Index. This is taken as the RESNET Reference Home. The lower a home rates, the more energy efficient it is. Therefore, a home with a rating of 70 on the HERS Index is 30% more efficient than the RESNET Reference Home. A rating of 130, however, is 30% less efficient than the RESNET Reference Home.

The RESNET HERS Index is the industry standard by which a home’s energy efficiency is measured. The HERS or Home Energy Rating System was developed by RESNET and is the nationally recognized system for inspecting, testing and calculating a home’s energy performance. Certified RESNET Home Energy Raters conduct inspections to verify a home’s energy efficiency and recommend improvements that can be made to increase it.