An apt resolution for builders in 2012 could be to follow the requirements of Energy Star Version 3. The new rules are now in effect for all homes seeking Energy Star certification with permit dates after Jan. 1, 2012, as well as homes permitted prior to New Year’s Day, but obtaining occupancy after July 1, 2012. Many of you were no doubt working with Version 3 under a voluntary pilot program--the eager, early adopting beta testers--thank you. Because of you, Energy Star has just released Revision 05, incorporating many refinements to make Version 3 not only more reliable, but builder-friendly.
Highlights from Version 3, Revision 05
You can find Revision 05 of the Version 3 guidelines now at http://www.energystar.gov/index.cfm?c=bldrs_lenders_raters.nh_v3_guidelines. Partners are permitted to use this revision immediately, at their discretion, but must apply this revision to all homes permitted on or after March 15, 2012.
The most substantial updates are summarized below:
Thermal Enclosure System Rater Checklist
- A new alternative to meeting 2009 IECC insulation requirements has been provided for homes that achieve ?
50% of the infiltration rate defined in the Energy Star Reference Design.
- The timeline for complying with the minimum insulation levels required at attic eaves has been extended.
- In the interim, homes with space constraints are permitted to meet less stringent levels.
- Drywall adhesive (but not other construction adhesives) may now be used to seal drywall to top plates.
- Foam sealant may now be used in place of caulk to seal sill plates to foundations or sub-floors. Note that a foam gasket is still also required beneath the sill plate if resting atop concrete or masonry and adjacent to conditioned space.
- Batts that completely fill floor cavities enclosed on all six sides may be used, even when compression occurs due to excess insulation, as long as the R-value of the batts has been appropriately assessed based on manufacturer guidance and the only defect preventing the insulation from achieving the required installation grade is the compression caused by the excess insulation. This policy replaces the list of specific permutations of R-values and cavity depths that are permitted to be used.
- The methodology for evaluating compliance with the reduced thermal bridging requirements for mass walls that are not part of a passive solar design (e.g., CMU block or log home enclosure) has been clarified.
HVAC System Quality Installation Contractor Checklist
- Until credentials are available specifically for heating, cooling, and ventilation system designers, either the builder (or a firm or HERS rater hired by the builder) or the credentialed HVAC contractor (or a firm or HERS rater hired by the credentialed contractor) are permitted to design such systems and to complete sections 1 through 5 of the checklist. As always, the designer must comply with applicable codes and laws that regulate HVAC designers and HVAC designs. In all cases, sections 6 through 12 of the checklist may only be completed by a credentialed HVAC contractor.
Energy Star offers free webinars to help builders prepare for, and understand the new requirements of Version 3. These webinars are a more palatable way to get your head around this update than reading the terse guidebooks.
Version 3 includes more rigorous training requirements for builders, raters, and HVAC contractors. EPA requires that each complete training on Version 3 to promote successful adoption and has created a number of resources to assist understanding the guidelines. The PowerPoint provided for training contains many useful details on how to solve common construction conundrums, such as insulating tubs, behind fireplaces, attic access hatches, and attic knee walls.