Design Energy Code Equivalent % Savings
 

Related section:  Baseline Guidance


The Design Energy Code is an input in General Inputs section 1. For whole building projects with the value of the "Energy Model Status" input field of "Will NOT be Modeled" or "Will be Modeled", but the "Has the project established an EUI yet?" is not checked, the Design Energy Code selection determines the SAVINGS for the project.  The SAVINGS percentage is a code equivalent % savings of the selected code to the code basis for the 2030 Challenge, which is CBECS 2003.
 

The Design Energy Code Equivalent Percentage Savings values are based on a collaboration with New Buildings Institute, which utilizes the code determination analysis by Pacific Northwest National Laboratory (PNNL) for each new version of ASHRAE Standard 90.1 to establish zEPI scores that ultimately become the code equivalent savings (100 - zEPI).    

The AIA 2030 DDx Design Energy Code Equivalent Percentage Savings can vary over time, due to one or multiple of the following:
- Significant new research has been made available: An example is when ASHRAE started using 90.1-2004 as the baseline for their calculations to assist making new versions and versions of other codes comparable to a single version.  Leading up to this shift, additional research and analysis was completed to assess what the percentage savings between 90.1-2004 and CBECS 2003 (baseline for 2030 Challenge) should be.  An adjustment was made, which had a ripple effect across a number of design energy codes.  That update has now been incorporated into the DDx.


-  Difference between the Pre-Publication and Final determination of % savings:  The timing of the PNNL final determination can vary, but they tend to issue a pre-publication notice near the release of a new ASHRAE version.    The pre-publication value will be associated with the design energy code initially, and it will be updated (if required), after the final determination has been published.
- Additional research and analysis has been provided to AIA for regional and/or international codes that warrant the value to be updated. 

 

Changes to the code equivalencies will only be updated at the point of saving and will not get updated across your projects unless you re-save the projects.

Design Energy Code Percent Reduction vs. Modeled pEUI Percent Reduction

  • If the % savings pEUI reduction for modeled projects is less than the design code % saving equivalent, consider adjusting your baseline so that you are meeting the design code equivalent % savings.
  • If using code equivalent savings the selected design energy code will drive the % savings
  • If a project has an energy model or will have an energy model, the % savings is derived from the pEUI and the baseline EUI.
  • If a project has an energy model or will have an energy model, check to make sure the % savings is a reasonable number – comparing to the code equivalent % savings is a helpful benchmark.
  • If the % savings value is unexpected, reevaluate and consider adjusting the baseline EUI.

Design Energy Code Equivalents

Design Energy Code

Approximate % Reduction from Average

ASHRAE 90.1-1999

10%

ASHRAE 90.1-2001

10%

ASHRAE 90.1-2004

25%

ASHRAE 90.1-2007

31%

ASHRAE 90.1-2010

42%

ASHRAE 90.1-2013

46%

ASHRAE 90.1-2016

50%

California Title 24 2005 for high rise residential

35%

California Title 24 2005 for single family residential

30%

California Title 24 2008

40%

California Title 24 2010

40%

California Title 24 2013

48%

California Title 24 2016

53%

California Title 24 Non Residential 2008

40%

California Title 24 Residential 2005

35%

California Title 24 Residential 2008

40%

IECC 2003

10%

IECC 2006

20%

IECC 2009

31%

IECC 2012

42%

IECC 2015

46%

*NECB 2011

45%

Older than 1999

0%

Massachusetts Stretch Code

52%

Oregon Energy Code

25%

Oregon Energy Code 2010

34%

Oregon Energy Code 2014

40%

Oregon Energy Efficiency Specialy Code 2010

25%

Oregon Energy Efficiency Specialy Code 2014

40%

Washington Energy Code

25%

Washington Energy Code 2012

25%

Washington Energy Code 2015

48%

 

Note: These are estimates of code comparison based on analyses by Pacific Northwest National Laboratory, New Buildings Institute, and Architecture 2030. These percentages are provided to enable the inclusion of non-modeled projects in analysis for the AIA 2030 Commitment.

 

*Source for this code is from the National Research Council Canada and New Buildings Institute.