Last September, the Environmental Protection Agency released new guidelines for Energy Star-qualified homes. The guidelines establish standards that respond to significant changes in residential energy codes and standard building practices.

The old Energy Star guidelines qualified homes that are 30 percent more efficient than the 1993 Model Energy Code. With significant changes to the state energy codes in the past 12 years, many Energy Star-qualified homes do not meet even local standards. The old guidelines required only that the home receive a Home Energy Rating System (HERS) score of 86 out of 100 or that it meet the prescriptive requirements of the Builder’s Option Package. These approaches aim to require good insulation and windows and tight construction and ductwork but fail to mandate minimums of R-value, air leakage or quality construction. So a home with very efficient windows but leaky ductwork and poorly installed insulation still could attain the Energy Star label.

The new Energy Star guidelines attempt to remedy these loopholes. By Jan. 1, 2007, all Energy Star-qualified homes will be at least 15 percent more efficient than the state energy code. And there will be more oversight by the HERS rater. Each home will be required to have a thermal bypass inspection to make sure the home is properly air-sealed and insulated. All insulation must be installed according to manufacturers’ recommendations to comply with the guidelines, or it will not receive an Energy Star label. The software program also has developed a protocol for downgrading the R-value (resistance to heat flow, which describes the capacity of insulation materials) of the insulation depending on the quality of the installation. The new requirements establish minimums for duct and envelope leakage, a big source of inefficiency.

Energy Star will require that all cooling equipment be sized according to the Air Conditioning Contractors of America’s Manual J, which assesses the size of a heating or cooling system a house needs. The HERS rater will require that a copy of the cooling-load calculation be submitted for each home to be certified. This is of particular benefit in our region of Western North Carolina, where oversized cooling equipment can lead to excess moisture, humidity, mold growth and high utility bills.

Starting in January 2006, 13 SEER (Seasonal Energy Efficiency Ratio, which describes the efficiency of heat pumps and air conditioners) became the minimum efficiency of cooling equipment manufactured. While this is not due to EPA-imposed minimums, it will make it more difficult to achieve the Energy Star label. This is because the program scoring works by allocating points for each aspect of the home that exceeds the energy code. Previously, with a 10 SEER code minimum, installing more efficient HVAC (heating, ventilation and air-conditioning) systems was an easy way to attain points. Now, only systems above a 13 SEER will receive points.

Another change to the program is the scoring system. The new HERS index will reflect energy usage instead of efficiency. So a score of 0 reflects a “zero energy home,” and a score of 100 is a home built to the 2006 International Energy Code.  An Energy Star home will still fall in a similar scoring range, about 85, approximately 15 points and 15 percent above code.

The new Energy Star guidelines still do not require, or offer points for, indoor-air quality measures or efficient lighting. But the EPA is developing an indoor-air quality package and offers an advanced lighting package for additional certification. The packages are great ways for builders to upsell their clients while building in durability, performance, comfort and low utilities in their homes. The basic Energy Star guidelines will, however, require that each home have at least one Energy Star-qualified product category, such as windows, HVAC, lights or appliances. That recognizes that energy use from lighting and appliances is a significant piece of the energy-use pie.

So what do all these changes mean for residential homebuilders and homebuyers? The next 12 months will be a “grandfather” period for the Energy Star program. HERS raters will begin to implement the new program standards, and by January 2007 all homes must comply. All certified homes must comply with the new guidelines unless they were enrolled in a utility- or state-based efficiency program by Dec. 31, 2005, or are permitted by July 1. However, local HERS raters may begin to implement the program immediately. Homebuilders need to contact their HERS rater to discuss how the new standards affect their construction practices and ability to attain the Energy Star label. By purchasing an Energy Star-qualified home, homebuyers can be more confident that the Energy Star label stands for quality and efficiency. For more information visit www.EnergyStar.gov.

[Maggie Leslie is treasurer of the Western North Carolina Green Building Council and is a consultant for builders interested in high performance and green building with an Asheville-based HERS Rater, Home Energy Partners. She can be contacted at or 350-1155, ext. 305.]