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Community and Q&A

BEOpt and IECC 2015

Ethan ; Climate Zone 5A ; ~6000HDD | Posted in Building Code Questions on

Does anyone here have experience submitting BEOpt data to show IECC 2015 compliance? Having already built a BIM model and a BEOpt model, and insomuch as I am planning to build well beyond code minimum, I believe that somewhere hidden in my BEOpt data must be a route to energy code compliance… I just have to figure out how to submit it.

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  1. Ethan ; Climate Zone 5A ; ~6000HDD | | #1

    BEOpt help says:

    The Energy Rating Index (ERI) is calculated per the ANSI/RESNET 301-2014 "Standard for the Calculation and Labeling of the Energy Performance of Low-Rise Residential Buildings using the HERS Index" as well as the ANSI/RESNET 301-2014 Addendum A-2015 "Addendum on Domestic Hot Water (DHW) Systems". This metric is a performance compliance path in the 2015 IECC.

    This output metric is only available if ERI has been checked on the Run Dialog.

    I have checked this box but still don't see ERI (HERS) info...

  2. Ethan ; Climate Zone 5A ; ~6000HDD | | #2

    Hello everybody! I figured this out, and thought I'd post info here for posterity. According to RESNET "Energy Ratings Index Performance Path" you can submit an ERI Score as part of the IECC 2015 Compliance path. This score is created in BEOpt if you check the appropriate box before running your simulation. As of this posting, the required ERI Scores are:

    • Climate Zone 1: 52
    • Climate Zone 2: 52
    • Climate Zone 3: 51
    • Climate Zone 4: 54
    • Climate Zone 5: 55
    • Climate Zone 6: 54
    • Climate Zone 7: 53
    • Climate Zone 8: 53

    Please double check these, but this is for reference.

  3. Expert Member
    Michael Maines | | #3

    Thanks Ethan, great info. I use BeOpt regularly but still learn new things every time I use it.

  4. Ethan ; Climate Zone 5A ; ~6000HDD | | #4

    Michael - What I can't seem to do is get BEOpt to allow for 100% Minisplit heating. It always wants electric baseboard backup. Maybe I need to tweak the minisplit data itself? I'm just using the stock minisplit values.

    1. Expert Member
      Michael Maines | | #5

      Ethan, same here and I'm not sure why. I select the 12kBtu "automatically size for load" option with electric baseboard backup. I like the cost of BEopt (free) and that it's fairly powerful and easy to use, but I'm thinking about upgrading to something in between it and the PHPP that I use sometimes. Before they had so many options for mini-splits I tried inputting my own data but it crashed the program, so if you go that route be careful.

      1. Ethan ; Climate Zone 5A ; ~6000HDD | | #7

        Maybe DOE can get some funding for a BEOpt software upgrade? What software are you considering?

        1. Expert Member
          Michael Maines | | #8

          Not to get political, but I was worried we would lose access to it entirely before Jan. 20. Upgrades would be good.

          Building nerd friends of mine use Ekotrope, Wrightsoft, RemDesign, Trace and other programs. I haven't spent much time looking into it yet. Martin wrote about options several years ago:

  5. Deleted | | #6


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