Energy Efficiency Wins Improvements to the Model Energy Code

December 24, 2019 | Jim Meyers

After a 12-month process the newest building energy code, the 2021 IECC, was recently approved by code officials through the online voting phase — by and large, they voted to increase efficiency gains not seen since the 2009 and 2012 energy code.

The International Energy Conservation Code (IECC) is the model building code for anyone involved in construction of energy efficient, affordable, and healthy homes and commercial buildings. The code is updated every three years through a stakeholder process involving code officials, builders, efficiency advocates, and others. The process for developing the newest code was first reviewed in April by a committee selected by the International Code Council (ICC). In October, public hearings were held where anyone could speak for or against changes. In early December the final vote by governmental ICC members took place.

The 2021 IECC is a huge gain for commercial and residential efficiency and a big step toward putting our nation’s model energy code on the glide path to net zero energy buildings. Energy savings of at least 10 percent are projected for buildings constructed in accordance with the 2021 IECC. As we saw with the big increase in energy efficiency after the 2009 code was approved, we anticipate big gains with the 2021 IECC. Critics of the new code are likely to complain that the changes are too expensive and an obstacle to building more affordable housing. We do not believe that to be the case, especially over the long-term.

Fast forward to 2019 and we see that many jurisdictions in the Southwest adopted energy efficiency measures recommended in the previous code 2015 to 2018 IECC. The complaints we heard ten years ago have been addressed and the building industry has a much better understanding of energy efficiency practices required in the newer IECC. The same concerns may arise with the 2021 IECC.

The voting results released by ICC are preliminary, and the votes must be certified and confirmed by the ICC Board of Directors, which will happen in the upcoming months. For the most part, we expect the 2021 IECC to reflect outcomes from the online vote. The new version of the 2021 IECC will be published sometime in mid-to-late 2020.

Energy efficiency highlights from 2021 IECC include:

  • Energy improvement: Lead by EECC and many other stakeholders an anticipated 10% energy savings over the 2018 IECC will be realized in the 2021 IECC.
  • Electric vehicle infrastructure: Developed by SWEEP, ASE, EEI and NBI, the provisions allow commercial, multifamily, and possibly single-family buildings to support current and future needs for EV charging.
  • Support to electrify building: Developed by NRDC, the proposal ensures buildings can easily switch to electricity from fossil fuels for space and water heating.
  • Commercial building efficiency: Lowers energy requirements by 5% when using the performance/software modeling path.
  • More flexibility for builders to comply with the residential code: Additional option packages will become part of the code for residential construction and increased options for builders to reach higher efficiency. This aligns with a section in the commercial code.
  • Two zero appendices; one to support local code adoption for a zero carbon path and another for a residential zero energy path.
  • Solar ready appendix for commercial buildings will now include storage readiness.
  • Lighting improvements: Efficiency and lighting controls will become part of the exterior lighting requirements for multifamily exterior lighting. Up to this point low-rise multifamily buildings have not had the same lighting requirements as commercial buildings. And the lighting requirements for commercial buildings have increased.
  • Building enclosure changes: Increased efficiencies in walls, foundations, air leakage.
  • Residential Water Heating: Now compact designs with centralized, minimal distance between hot water source and the faucets/outlets.
  • Residential insulation requirements: Some climate zones will see more efficiency from insulation in the building enclosure.
  • Improved residential air sealing requirements: By clarifying and improving the language, builders and trades will have a better opportunity to air seal homes appropriately.
  • ERI pathway: The total performance pathway for new residential buildings will see new ERI scores, the backstop for the building enclosure efficiency is updated.

SWEEP worked with many southwest stakeholders to inform them of the 2021 IECC process, the opportunities for efficiency improvements in the code, and provide insight into the some complex (to a non-code development person) ICC process to update the energy code. We are still digging into the outcomes with modifications proposed along the code development path, but we believe the efficiency improvements will become substantial for Southwest states and municipalities with the adoption of this IECC.

We thank the state energy offices, building officials, and sustainability departments who sought our assistance and asked direction on where to find valuable information to make wise decisions when participating in the process. The energy code is the foundation for all buildings to reach zero energy while also supporting states and localities with their environmental goals.

Jim Meyers is the Buildings Program Director at SWEEP. He is responsible for conducting analysis, preparing case studies, evaluating new and emerging technologies for buildings, and promoting the adoption of state-of-the-art building energy codes.