A proposed change to the 2015 International Energy Conservation Code (IECC) would give builders greater flexibility to meet the code’s requirements, saving time and money while potentially leading the way for greater code acceptance in the future.

The change would allow builders to meet the code via a performance-based approach—using a new metric called the Energy Rating Index (ERI)—rather than meeting a detailed prescriptive checklist. The Home Energy Rating System (HERS) score, which qualifies as an ERI, would be the most likely method for compliance.

The code change proposal sets target ERI scores from 59 to 63, depending on climate zone, says Meg Waltner, building energy policy manager for the Natural Resources Defense Council (NRDC), a supporter of the proposal along with the Leading Builders of America (LBA), the Institute for Market Transformation (IMT), and the Britt/Makela Group. Under the initiative, builders who select the ERI option would be required to meet specific mandatory envelope and hot water (such as pipe insulation) requirements, but would have the flexibility to achieve the target ERI by the most cost-effective means available.

The performance-based approach would allow builders to select the efficiency measures that cost the least and perform the best for each project, according to an NRDC blog posting. LBA estimates that a level of energy performance that would have cost $3,000 using the checklist approach instead would cost only $1,300 with the HERS score approach, including the cost of the HERS rating.

Supporters of the proposal say its passage would have implications for the future of sustainable home building. “With this in place we could then start talking about energy efficiency at a whole building level,” says Ryan Meres, IMT’s code compliance specialist. “That’s the type of discussion we’re going to have in order to be on the path to net zero.”

If passed, the initiative would help to make future code discussions simpler, adds Meres. “It will remove a lot of the special interests from code development,” such as manufacturers and suppliers interested in a code that dictates specific products or requirements. The proposed changes do not do away with the prescriptive path, which is preferred by smaller builders concerned about the cost of a HERS evaluation, which can add $300 to $1,000 to a project, Meres says.

Nevertheless, the initiative is seen as a win-win for builders and their customers, according to Meres. “By using this simpler, consumer-friendly rating system, a home buyer can understand the efficiency of the house and compare House A to House B,” he says. “Meanwhile, this also would give builders more flexibility in meeting market demand for more energy-efficient living.”

The updated code would save homeowners an estimated $300 annually for a typical new house compared to the 2012 IECC, which has been adopted in only a few jurisdictions, or $850 compared to the widely used 2006 IECC.

Building on its successful launch in 2012, ECOHOME’s Vision 2020 program continues in 2013, focusing on eight critical areas in sustainability. Track our progress all year as our panel of visionary focus-area chairs, our editors, and leading researchers, practitioners, and advocates share their perspectives on initiating, tracking, and ensuring progress toward sustainable priorities and goals in residential construction between now and 2020. The program culminates in an exclusive Vision 2020 Sustainability Summit in Washington, D.C., in September 2013, and with a special edition of ECOHOME in Winter 2013. Click here to see the 2012 Wrap-Up.