In 2010, EPA released new, Version 3 guidelines for the ENERGY STAR for Homes program that will allow ENERGY STAR to continue to define energy-efficient home construction. The new guidelines incorporate a host of cost-effective energy efficiency technologies and building science practices that will improve the efficiency, durability, and indoor air quality of ENERGY STAR certified homes. Homes built to the new ENERGY STAR Version 3 guidelines will be at least 20% more energy efficient than homes built to the 2009 International Energy Conservation Code (IECC).

What are the primary changes?

With Version 3, homes must meet baseline ENERGY STAR requirements, still using either a prescriptive or performance path. Both options are based on a set of specifications called the ENERGY STAR Reference Design. When the prescriptive path is used, the home is simply built according to the Reference Design specifications (similar to the Builder Option Package approach used in ENERGY STAR Version 2). No trade-offs are allowed when the prescriptive path is used.

In contrast, the Version 3 performance path has been significantly changed from the Version 2 approach. Using the Version 3 performance path, the home is modeled using the ENERGY STAR Reference Design specifications to establish an Initial Energy Rating Index Target Score. For larger homes, a Size Adjustment Factor (SAF) is applied to the Initial Target Score when the home exceeds a defined ’Benchmark Home Size,’ based on the number of bedrooms. The builder then has the flexibility to select a custom set of energy-efficiency measures, so long as the resulting ERI Score for the home meets or performs better than the Energy Rating Index Index Target Score (size-adjusted, when appropriate) and all other requirements are met (e.g., minimum efficiency for windows, insulation levels).

In addition to the baseline requirements, there are new checklists with detailed mandatory requirements for Thermal Enclosures, HVAC Quality Installation, and Water Management. Note that there will be other customized requirements in states where the energy code exceeds the 2009 IECC.

What is Version 2.5?

Version 2.5 is a transitional specification in which homes must follow the Version 3 requirements, with some exceptions. For more information about the transition from Version 2 to Version 3 guidelines, see the Transition Timeline. EPA envisions the ENERGY STAR Version 2.5 guidelines as an important opportunity for partners to have a period of transition to the more rigorous Version 3 specification. EPA believes that partners should take full advantage of this phase-in period to ensure a smooth transition to the new guidelines, in particular the requirements of the new inspection checklists.

What if I want to implement Version 3 during 2011?

EPA has established a policy that no homes may be certified under Version 3 until January 1, 2012. The exception to this policy is where a utility or state sponsor is mandating or incentivizing early adoption of Version 3 in their area. In these cases, EPA will allow the labeling of ENERGY STAR Version 3 homes prior to January 1, 2012 on a pilot program basis, provided that the sponsor meets certain requirements.

How will these changes impact utility ENERGY STAR for Homes Programs?

More detailed verification of efficiency measures: The new ENERGY STAR Version 3 checklist allow for a higher level of verification that will provide sponsors with greater assurance that efficiency measures are being properly installed and that ENERGY STAR certified homes meeting performance and quality expectations.

  • The Thermal Enclosure checklist will help ensure that there are no thermal defects.
  • The HVAC Quality Installation checklists will help ensure that HVAC systems are installed using industry best practices and perform at rated efficiencies.
  • The Water Management builder checklist will help ensure roofs, walls, and foundations are fully protected from water intrusion.

Greater savings per home: ENERGY STAR Version 3 homes are approximately 20% more efficient than homes built to the 2009 International Energy Conservation Code (IECC). As a result, ENERGY STAR certified homes under Version 3 will be approximately 15% more efficient than homes built under Version 2. Further, the size adjustment factor ensures that larger homes include additional energy efficiency measures to account for their added size.

More definitive savings: Demand and peak savings will be much more reliable with every certified home due to greater rigor of the Reference Design and mandatory checklists. As a result, there will be less opportunity for builders to omit important energy efficiency improvements, and utilities can more confidently quantify the specific savings associated with ENERGY STAR certified homes.

Continue to leverage nationally recognized ENERGY STAR name: More than 75% of households recognize the ENERGY STAR logo, with even higher awareness in areas where utilities are actively promoting the brand. ENERGY STAR makes it easy for homebuyers to select energy-efficient homes. Efficiency programs based on ENERGY STAR benefit from this awareness, and offer a straightforward framework for designing incentive structures. Builders also benefit from being able to leverage ENERGY STAR for effective differentiation from the resale market.