Energy Performance Point Calculation Streamlined for the National Green Building Standard

Originally published by: NGBSMarch 19, 2015

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Based on builder’s action, it was clear there was a disincentive for builders to utilize the NGBS Performance Path for certification due to the fixed 30-, 60-, 80-, and 100-point allocations. For example, a home that was 28% more efficient than the 2009 IECC—below the 30% threshold—would be scored as if it was only 15% more efficient (30 points), giving no point benefit for significantly higher performance. This resulted in some builders opting for the Prescriptive Path to ensure the points they received were commensurate with higher efficiencies in their homes.

The intent of revisions to the NGBS is to provide approximately equivalent paths for Performance and Prescriptive, and in cases like these it did not. Point allocation have been realigned for Section 702-Performance Path in order to rectify this identified imbalance. As a result, two points are now available for each percentage point better the home is than the IECC. So a home that is 28% better than the IECC receives 56 points, rather than 30. The maximum total points for 702.2.2 is still 100.

Always be sure you are using the most current version of the NGBS Green Scoring Tool so you can take full advantage of streamlined scoring.