Home Builders Use the HERS Ratings for ERI Compliance
Builders in 15 states have an alternative path to meet 2015 IECC building code requirements.
The Energy Rating Index is an optional compliance path that is part of the 2015 International Energy Conservation Code, and will be part of the 2018 code as well.
The voluntary ERI compliance path for the 2015 IECC gives builders the option of complying with the code by meeting a target Energy Rating Index score. This is a numerical score where 100 equates to the efficiency levels prescribed in the 2006 IECC and 0 is equivalent to a net-zero-energy home.
Each point on the ERI scale represents a 1 percent change in the relative energy efficiency of the building. Each point higher is 1 percent less efficient and each point lower is 1 percent more efficient.
One example of this score is RESNET’s Home Energy Rating System (HERS). In addition to meeting the ERI target for a home’s climate zone, under the ERI compliance path a builder must also meet minimum envelope requirements not less than the 2009 IECC levels.
Many builders have decided to get an energy rating index for their homes because it provides a market advantage which is beginning to get recognized by many Multiple Listing Services (MLS). In fact, there are MLS’s in more than 10 states that allow ERI scores to be included in the listing.
RESNET reports that using the ERI performance path could save about $468 per year over a comparable house built to the 2012 IECC. In addition, the ERI performance path will deliver 20 percent savings in utility bills compared to the 2012 code and 40 percent savings compared to the 2006 code based on Natural Resources Defense Council (NRDC) estimates.