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Community and Q&A

When States Jump Ahead in IECC Adoption

cold_feet | Posted in Building Code Questions on

When states are more than one increment behind in their building code adoption, is there harm in jumping all the way up to the most recent version?  E.G., take any of the 39 states that are currently using the 2009 residential IECC or older.  Would it be realistic for many of them to move directly from 2009 (or older) to 2018 IECC?  If not, how would you recommend your state catch up if it was a decade or more behind?

Looking at the residential side of this map made me realize how far behind most states are in IECC:

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  1. b_coplin | | #1

    Harm to whom? How is harm defined?

    There are costs to training some contractors may not be able to absorb, which could put some out of business. Housing may become more expensive (first cost). It could also be argued that substandard housing is a public subsidy of mediocrity.

    1. Expert Member
      MALCOLM TAYLOR | | #2

      "It could also be argued that substandard housing is a public subsidy of mediocrity."

      That's extremely well put.

    2. cold_feet | | #3

      Is it realistic for a state to jump two, three, four versions/increments/releases (whatever the relevant term is) at a time?

      What anti-lobbying (barriers to adoption) would you expect local or state officials to have to be prepared for if they wanted to move from say the 2009 residential IECC to the 2018 residential IECC?

      1. JC72 | | #5

        A couple of things. No 1 - States and local governments can "adopt" the most recent code and then make their own revisions to individual portions within it. For example of current code requires 3 ACH the state/local govt may choose 5 ACH as the limit.

        The biggest friction point on building codes is COST. Cost in terms of materials, skillset of your labor and time (in terms of labor hrs). The vast majority of detached single family homes in the US are built by production builders. Their business model revolves around building a home as efficiently as possible for a customer base that does not place energy efficiency or occupant comfort as a primary need.

        IMO the biggest pain point is air infiltration. Once you get under 5 ACH (IIRC) the house needs mechanical ventilation and the cheapest solution to mechanical ventilation is "supply only" which is also the worst option. A dedicated duct system with HRV/ERV really is the only way to go but it adds a lot of cost. Not to mention that the HVAC system needs to be sized and built correctly.

        Exterior insulation is the other pain point because it really slows down the build.

        Some states, because of their climate, have an easier time at adopting most recent code. California for example. Their climate is conducive to solar so builders are meeting current EE code by throwing panels on the roof rather than building significantly better structures. You couldn't use that approach in Minnesota.

        Finally build codes are simply rules. If an older code specified R13 for a wall and current code says R21 the current code isn't "harder".

  2. Deleted | | #4


  3. Expert Member
    BILL WICHERS | | #6

    I suppose you could jump a few revisions at once and have a longer code update class that year. I don’t see that being a huge problem.

    Since I’m most familiar with the electrical side since that’s what most of my work involves, I can tell you that many code updates aren’t exactly “better”, they’re just “different”. Many new codes are driven by vendors wanting to sell their products too. If you’re a manufacturer, and you can get your product written into the code somehow as a requirement, that’s so awesome for your bottom line! Now EVERYONE is REQUIRED to buy your product! Not such a great deal for the contractors, builders, home buyers though.

    Some codes make sense, or do help in some way. More attic insulation is a good example: it’s not that much more money to go from R38 to R49 when installing blown insulation, so it’s a relatively cheap upgrade with some bang for the buck. Going from R10 to R15 on basement walls in CZ5 though has a MUCH lower return on investment for MUCH higher relative cost increase though, and there are even some studies (U Minnesota I think it was) that basically say it’s not worth it. Mandating new lightning connectors in California so people couldn’t possibly use a different light bulb is another example.

    I think code updates that are reasonable and have some tangible benefit are usually a good thing, but you don’t want someone’s agenda getting written into the code since that’s where you get waste. I suppose that deviates a bit from the original question of “skip a few revisions” and gets more into the “why IS there a new revision” issue though :-)


  4. Deleted | | #7


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