When it comes to building sustainably, there are many different ways to go about it, and even more when considering all of the possible certifications that get tossed around. But what do all these certifications and terms mean? Some may be similar, but they aren’t all interchangeable.
Home Energy Rating System (HERS) Index: This is the industry standard for measuring a home’s energy efficiency, and is a nationally recognized system used to inspect the energy performance of a home. Homes receive an index score from between approx. 150-0 and the lower the index score, the better. According to the HERS website, homes on the resale market typically receive a score of 130, while standard new homes receive a score of 100. A home with an index score of 0 (or less) has achieved zero net energy.
Our homes are given a HERS score at the end of each build. You can see the scores of some of our previous projects HERE.
Net-Zero Energy/Zero Net Energy: These low energy homes produce as much energy as they use within a year and are carbon-free. Net-Zero can be achieved by high insulation, air-tightness (such as from quality windows and doors), and the use of solar panels and energy efficient products for HVAC, water heaters and lighting.
Leadership in Energy & Environmental Design (LEED) Certification: The most widely used and globally recognized rating system for green buildings. This certification is available for any building type in any phase of construction.
Passivhaus (Eng. Passive House): Homes that are Passivhaus certified are low energy and energy efficient. These homes can also be net-zero, but a net-zero home isn’t necessarily qualified as passivhaus, as these homes are all about the design aspect, and use specific techniques during the build process in order to make a home, well, passive. This means using materials with high insulation, natural heating methods like optimal window position for increased sunlight, passive solar, superior ventilation, etc.
Energy Star: A government backed certification for not only homes, but also household products and appliances. An energy star certified product will be more energy efficient and cost-effective than others on the market and work well when trying to build a net-zero home, or when trying to reduce costs in an existing home.