Stretch Codes: A Key Tool on the Path to Carbon Neutral Buildings

Adopting energy codes that go beyond the base, or required minimum code, is proving to be an effective way to achieve energy savings and reduce carbon emission from the built environment. We have long been hearing about states such as Massachusetts, Rhode Island, California, Vermont, and New York, which have adopted stretch codes as a way to allow their cities to put new construction on a path towards greater energy efficiency and carbon reduction.

With the new President-elect supporting a 100% renewable electric grid by 2035, stretch codes are poised to play an even more important role in helping cites, states, and the nation achieve carbon neutrality. Widespread adoption of new construction stretch codes by cities is one opportunity and an important first step to realizing our nation’s climate objectives.

With the adoption of two appendices, the Zero Energy Home Appendix and the Zero Code Commercial Appendix, into the 2021 International Energy Conservation Code (IECC), cities and states now have the ability to adopt code language for new construction that ensures buildings reach zero energy and zero carbon emissions, or close to it. (Visit our previous blog to read about other changes to the IECC.) The 2021 IECC appendices will be available to U.S. cities starting in January 2021. The big question is: How many jurisdictions will grab this opportunity, and when?

Stretch codes help with market transformation

Community Adoption of the Stretch Energy Code; “Appendix 115 AA” of the MA State Building Code (780 CMR). Provided by the Massachusetts Department of Energy Resources.

A stretch code is a locally mandated requirement, or alternative compliance path, that is more aggressive than base code. Adopting a stretch code gives cities and states the ability to accelerate actions focused on saving energy and reducing greenhouse gas emission from the building sector. Stretch codes can be used to achieve other objectives, too, such as  prohibiting gas-burning appliances, which have known emissions that cause human health problems, and managing load demand on the grid.

Jurisdictional stretch code programs are often aligned with utility energy efficiency programs and incentives. In most cases, states develop a model stretch code that cities can then adopt as their base energy code. For example, Massachusetts became the first state in the nation to adopt stretch code as an above-code appendix. Since 2009, more than two-thirds of the towns in Massachusetts have adopted their model stretch code. In California, which started the original CALGreen Reach Code in 2009, dozens of cities  are now using reach codes to both reduce carbon emissions in the building sector and electrify buildings, which improves air quality both inside and outside their homes and buildings.

In New York, where Governor Andrew Cuomo’s Green New Deal and the Community Leadership and Climate Protection Act of 2019 set the state on a path to carbon neutrality, the New York State Energy Research and Development Authority (NYSERDA) has launched NYStretch Energy Code – 2020 (NYStretch), an above-code standard that New York municipalities are voluntarily considering  to adopt – or have already adopted, as in New York City. Analyses demonstrate that NYStretch will be 10 to 12% more efficient than the 2020 NY minimum code. NYSERDA provides a suite of tools and support to help  communities understand and implement NYStretch.

Stretch codes give jurisdictions the ability to familiarize the design and construction communities in advanced practices before the base energy code is improved. Engineers, architects, builders, and developers can access standardized specifications and become experienced with, and often receive incentives for using, innovative designs, products, and practices that they might not otherwise apply. Because the base code is updated every three years, adopting a stretch code gives jurisdictions and manufacturers of building materials, mechanical systems, lighting, and other technologies time to prepare before the base code “catches up” to the stretch code requirements (i.e., it gives them a head start).

State policy changes could empower cities

Boulder, Colorado, has been one of the leading jurisdictions in stretch code adoption.

More than 30 states have adopted a renewable portfolio standard, many of which aim for 100% clean renewable electricity. Some cities and states have built on that momentum by adopting stretch codes. In states that are lagging behind, there are cites (Boulder, Colo., for example) establishing their own energy code at advanced stretch levels. This is only possible because the State of Colorado does not place any statutory limits on city energy code. That is not the case, however, in over two dozen other states, which preempt their cities from adopting stretch codes.

Cities bound by these preemption rules face a significant barrier to adopting advanced stretch codes. Right now, cities such as Minneapolis, Portland, Ore., and Geneva, Ill., have to seek other measures to meet the emission reduction goals of their climate action plans — unless they take their case to state legislatures and win. We expect to see this issue come up more in 2021, especially in Minnesota, Illinois, and Connecticut where cities have established climate action objectives for the building sector.

The climate leadership of President-elect Biden and his support for a carbon neutral building sector should accelerate the role of stretch codes as a key state and local climate policy lever. A carbon neutral building sector was only a dream 10 years ago. But with the costs of clean energy production beating its competitors and the techniques for low-energy construction gaining traction in many markets, it is only a matter of time before our policies catch up. And stretch codes are a key policy tool available today (where not preempted by state law) for taking that important step towards carbon neutrality for all new construction.

by Jim Edelson, Director of Policy
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