Written By: Athena Seay
HERS stands for Home Energy Rating System. The HERS Index is the industry standard by which a home’s energy efficiency is measured. It accounts for all of the energy used in the house including lighting, appliances, framing, insulation, air sealing, water heating, and HVAC.
The HERS rating process is governed by an organization called RESNET, Residential Energy Services Network. This body is responsible for the national training and certification of Raters. It was established in 1995 as a non-profit organization to help homeowners reduce their utility bills by making their homes more energy-efficient.
How does the HERS Index work?
The HERS score is based on an Index, the lower the score the more energy-efficient the home. When RESNET started the HERS Index a standard new home would typically score 100. The Index is generated by comparing energy consumption from a standard new home, i.e. the reference home, based on the same size and shape as the rated home. If the reference home and the rated home use the same amount of energy the rated home will receive a 100 on the HERS Index. Therefore, a home rating of 70 is 30% more efficient than the reference home and a rating of 130 is 30% less efficient than the reference home. A certified RESNET HERS rater conducts testing and modeling at the beginning and end of the build to give an index score. Right now in NC and SC a code-built home typically achieves an 85 on the HERS Index, this is because energy codes are more stringent now than they were when the HERS Index was developed.
Performance Point recently had the opportunity to interview Laurel Elam, the Director of Quality Assurance Administration and Standards for RESNET.
Performance Point: Have you seen an increase in demand for HERS-rated houses, in the last year? Overall?
Laurel Elam: Yes, definitely! Despite a pandemic and a slow down of the U.S. economy, there were 24% more homes HERS rated in 2020 as compared to 2019.
In 2020, there were 299,755 homes in the United States that were HERS rated and issued a HERS Index Score. This broke the record for the number of homes HERS rated in a year. The previous record from 2019, were 241,664 homes HERS rated.
The average HERS Index Score in 2020 was 58. This is 42% more efficient than a home built as recently as 2006. In
2019, the average HERS Index Score was 59.
And we’re commemorating that over 3 million homes have received a HERS score to date. We’re spending the year celebrating with all of our partners and stakeholders who helped make this milestone.
PP: Is this increase in demand coming from builders, consumers, or code compliance regulations?
LE: All of the above, but mainly builders and code compliance regulations. What started in 1995 with just a few hundred homes rated per year, has now grown exponentially. By 2012, there were more than one million homes HERS rated, followed by another million homes by 2017, and now the milestone of over three million home HERS rated, a little over 3 years later. This upward trajectory of home buyers choosing to build more energy-efficient, comfortable and healthier homes is certain to continue.
PP: Does a lower HERS index score benefit the environment? How?
LE: According to the EPA calculator, the homes that were HERS rated in 2020 will reduce carbon dioxide emissions by over 1.3 million tons annually, which equates to 284,000 passenger vehicles being taken off the road for one year.
PP: What are some environmental goals that RESNET has for the future in particular with HERS?
LE: Continue to increase the demand for HERS ratings which lowers greenhouse emissions, etc. RESNET also drives demand for HERS H20 to reduce water usage in homes. Recently, we partnered with the One Tree Pledge (OTP) sustainability campaign on a unique new collaboration in celebration of the 3 millionth HERS rated homes. Together RESNET and OTP are launching a campaign with the goal of planting 300,000 trees to help combat climate change by the end of January 2023. The trees, over their lifetime, will naturally sequester roughly 3 million pounds of carbon from the atmosphere annually, helping to reduce greenhouse gas emissions. We invite everyone in real estate to get involved, from home raters and appraisers to realtors and mortgage brokers to donate to our tree planting initiative at a cost of only $1 per tree. Visit https://onetreepledge.org/resnet/ for more information.
PP: What is the relationship between RESNET and Performance Point?
LE: Performance Point is an accredited rating provider. This means they oversee their raters that provide home energy rating, this also includes Energy Star verification and we oversee the work PP does.
How can Performance Point help builders?
We can help you grow your business through marketing. Marketing that your homes offer lower energy efficiency. Yes, it costs more to build an efficient home, but customers are willing to pay more to see advantages every month through lower energy bills. A new study conducted by Freddie Mac found that homes that were HERS rated sold on an average 2.7% more than comparable unrated homes. In addition, homes that received lower HERS Index Scores sold for 3 – 5% more than homes with higher HERS Index Scores. The study also found that buyers of HERS-rated homes also have more desirable mortgage profiles.
Performance Point also can help you keep track of building code compliance regulations. We’ll educate you on products and suppliers to save you money. We’ll “model” your homes to explain what ways to net the most return on investment.
Be the go-to resource for programs and rebates. We know the opportunities for incentives and can submit these for you. (utilities, states, manufacturers).
It’s a win-win-win situation for builders, homeowners, and the environment!
Call us today! We are your RESNET verified HERS Rater.
Look for the final article in this series, Energy Star: What is it? How do you get certified and its impact on the environment.