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Published Mar 25, 2024
21 mins read

The Fight Around Building Codes

With Heat Pump Review , my intention is spend a big part of our time covering topics around the pace at which heat pump technology is being adopted; and while I've been writing about or preparing to write about the important role of transparency , installer participation, impact of tax credits, and access to financing, one topic I had not been thinking about until last week was that of local building codes and how they impact this transition. Some big news last week out of the International Code Council (ICC) has forced me to confront that gap in my thinking, and gives Heat Pump Review the opportunity to start exploring the topic of building codes with you.

Intro to ICC and IECC Codes

Local Codes, Central Source

Anyone who's done a substantial home building or improvement project has probably run into their local codes and a final inspection from their municipality's code enforcement office. Perhaps you updated your deck and the contractor told you that the posts needed to be dug to a certain depth, or when you installed an oven hood you were told that the vent needed to exit the building at a certain pitch. My latest run-ins with codes were when we added solar to our roof and upgraded our electrical panel. These were simple and painless processes, as my contractors knew the code and did work according to the code, allowing the inspectors to be in an out within minutes.

So where do these codes come from?

While states and municipalities may invent their local codes whole cloth (at least in many cases; we'll talk about a legal concept called “Preemption” later), most jurisdictions rely on the codes published by a large and powerful non-profit called the ICC . Relying on a central body makes sense: instead of each jurisdiction spending resources to start from scratch and re-think every detail around building codes – potentially missing key codes that keep people safe and creating chaos for contractors new home builders, equipment manufacturers and homeowners in different parts of states or the country – many jurisdictions just start by adopting the minimum standards set by the ICC and then, on an ad hoc basis, add to or change the codes where they see fit. As the ICC updates their codes every few years, states and municipalities may decide to adopt the latest codes quickly, skip the version, or wait a few years to act. Some locales have laws on the books that proactively dictate the pace and mechanisms of adoption when new codes are published, while many less progressive locales adopt a code version (e.g., “the 2009 codes”) on an ad hoc basis and then keep them in place for decades, until there's an external / political reason to take action (e.g., highly publicized building collapse, pressure from insurance companies, complaints from industry lobby, etc). Google your city + ICC codes and you can quickly get a sense of where your city is on this cycle. I was surprised (and disappointed) when I saw that my present city of Baltimore – ostensibly one of the most progressive in the country – is stuck on the 2015 code , adopted nothing from the more ambitious “Appendix” section of the Efficiency codes, and only amended the code to strip some sections that cover things like fees and appeals the city had existing regulations around.

The Code Book's Appendix

When the ICC publishes new code, they have the main body for minimum standards, but they also have an Appendix with additional code for the most intrepid/progressive municipalities to adopt. Because so many places adopt only the minimum standard, whether a code gets placed in the main body of code or the Appendix turns out to be enormously consequential for whether only the Seattles of the country adopt a new code or if everyone (eventually) does; and therefore the placement of codes is highly political as well. The transfer of some critically important efficiency codes from the body of the 2024 codes to the Appendix is at the center of the ICC's actions this week (which we will cover below).

IECC International Energy Conservation Code (IECC)

ICC is an enormous body of code , and within that body there are dozens of acronyms: IFC is the International Fire Code, IPSDC is the International Private Sewer Disposal Code, ISPSC is the International Swimming Pool and Spa Code, etc.

And so, when we talk about ICC codes and those that dictate energy appliances (including the insulation and weather sealing that make those appliances work), the codes we care most about are the IECC (International Energy Conservation Code); so in this post and others we may use ICC and IECC interchangeably. When reading about specific ICC codes you will also see prefixes such as R for Residential, C for Commercial, and the RE or CE for codes that govern work done on existing structures.

Role of the Federal Government


While most building codes are adopted and enforced at the local level, sometimes locally created regulations run into a legal issue called Preemption . The general idea behind Preemption is that state and local jurisdictions cannot pass laws/regulations that compete with constitutionally legitimate ones imposed by the Federal government. This is why so much is made of “ the California waiver ,” an amendment to the Clean Air Act, which explicitly allows California to set more stringent car emissions standards than our Federal ones.

The highest profile recent case of preemption and energy efficiency codes took place in Berkeley, CA, where the city tried to use their code to ban new buildings from having natural gas connections at all, causing the natural gas industry to sue the city. This case went all the way to the Ninth Circuit Court of Appeals, and Berkeley lost , with the court finding for the gas industry that the local code was preempted by the less climate and public health friendly Energy Policy & Conservation Act , or EPCA, (despite the Biden administration arguing, on behalf of the Federal government itself, that the act did not preempt the ban). Threats and concerns about lawsuits around preemption are the second major center of concern for this week's actions by the ICC Board (again, to be covered in detail below).

HUD Loans

Beyond legislation and preemption, the second way the Federal government can influence codes is by deciding on which codes/standards are required in order for a newly constructed home to qualify for a federal loan (about 1/5th of all loans for new homes are originated with the Dept of Housing and Urban Development , aka HUD ).

By setting standards for new home purchases at a certain level, the Federal government can indirectly prod more recalcitrant local authorities to adopt codes that impact all new homes. HUD does this by creating incentives for the homebuilders in the area to use more modern codes than might be locally required, in turn giving local industry a reason to pressure their governments to update codes for the benefit of consistency. Whether or not the Federal government exercises this power is dependent on the administration in power. For a quick history of the law that allows for HUD to set codes, see this Alex Kaufman article in The Huffington Post; but to give you a sense of how long codes stick around in the system, the last time HUD adopted an ICC standard was in 2015 when President Obama made the 2009 codes the requirement. Apparently (per Alex's article above), President Biden has promised to update the minimum code requirement to the 2019 rules, but he is late in doing so and activists aren't quite sure what's taking so long. Until then, HUD will keep holding builders to efficiency standards that are now 15 years old, and sadly those standards still might be higher than what are otherwise required in that jurisdiction.

ICC Membership, Consensus Committees & Governance

With all things that rule us, it's worth knowing more about who is behind the action and how that body works.

While I'll summarize what I've learned in this section, if you want a more knowledgeable and detailed view into the process I recommend listening to Dave Roberts' excellent, recent interview with Huffington Post writer Alex Kaufman . Dave's blog and podcast, Volts, is by far one of the best resources for all things climate + electrification, while Alex's work covering climate industries and especially this ICC / code issue has been comprehensive and important.

General membership to the ICC comes from all types of people, including members of the trade, municipal employees, engineers, manufacturers, and more. With a few hundred bucks, you or I could join and get full access to the codes at any time and be eligible to submit proposed code changes.

Then there are processes by which proposed changes to codes are adopted. As Dave and Alex discuss in the podcast linked above, the process by which ICC considers and adopts code changes has been changed and scrutinized a lot in the last 5 years. For the cycle that just concluded (the trigger for last week's news), code changes were mostly considered and then adopted by so-called Consensus Committees comprised of diverse sets of governmental members, policy experts, engineering experts, ICC staff, industry stakeholders and other “qualified” mostly volunteers from the community. These committees painstakingly considered hundreds of proposed changes during the code review cycle and then voted on a final recommendation. Codes needed over 50% to get out of each subcommittee and then 2/3rds support to get out of the full committee.

However, final adoption of rules happens at the Board of Directors, and the Board of Directors is elected by municipalities themselves. It's at this Board level where last week's news and controversy took place, specifically regarding the 2024 IECC codes.

The 2024 IECC Code Controversy

The big news last week hit when the ICC's Board of Directors voted on and then announced via Press Release their decision to strip several important new codes that made it through years of Consensus Committees work and were designed to be part of the main body of the code, moving them to the Appendix, while taking other sections out of the Appendix and moving them to an even less enforced section called “Resources.”

I struggle to call it a “controversy,” because that implies that there are two reasonable sides to the issue. I've read the appeal from the American Gas Association ( AGA ) and the appeal from the Air-Conditioning Heating & Refrigeration Institute ( AHRI ) that prompted most of the changes, and while I am very new to the topic and process, both appeals come off as transparent ploys to protect their respective industries (or in AHRI's case, to protect the incumbents in their industry) and run counter to the stated purpose of the ICC and IECC codes. 

While ICC's move was a shock to some, it was not unforeseen: Earlier this year, the ICC Board openly welcomed appeals of the work done by the Consensus Committees and – as it appears by design – quickly received official appeals from the gas (AGA) and HVAC (AHRI) industries, bypassing the ICC's own rules to have appeals go back to the Consensus Committees and instead making their decisions at the Board level, even ignoring the results of their own appeals hearings which initially rejected the claims. The whole appeals process – and the material questions regarding the process' legitimacy – was covered in great detail by Columbia Law's Sabin Center writer Daniel Metzger back on March 5th before the decision was made. House Democratic leadership also tried to intervene in early March, concerned that this decision would take place.

For another tick-tock of the recent few months, and the impact of last week's decisions, I recommend reading the bi-partisan American Council for an Energy-Efficient Economy (ACEEE) scathing letter published in response , or the account from the Institute for Market Transformation (IMT). After reading “both sides” it all just stinks.

What specifically got moved

Based on the appeals, the ICC Board unilaterally moved 15 sections to the Appendix that would have helped new homes and commercial buildings achieve energy efficiency targets by making them ready for modern electrification and solar appliances, and therefore less expensive for home and building owners over the long-haul. Examples of things the Gas industry took issue with were: 1) making sure that roofs are built in a way that will allow solar to be installed without requiring major modifications, 2) making sure appropriate electrical connections are wired to garages to make them “EV Ready,” 3) requiring electrical connections to be terminated at cooking and heating appliances even if the initial appliance is gas powered, and 4) making sure modern technology is used for residential water heaters and commercial lighting that allows them to use less energy when not in use (seriously: they objected to requiring cheap motion detectors that would turn off lights when people aren't at the office). The full list of sections moved is at the ICC press release linked to above, and you can cross reference it to the draft language still hosted on the ICC website ( Residential draft here ; Commercial draft here ).

The Board also moved 4 sections from the Appendix to the “Resources” section of the code (drafts of those sections also linked to above). These sections were codes that defined how a builder might create an “All Electric” building, as well as code examples that would help buildings become net zero emitters, if they wanted to.


The reasons the ICC Board gave for stripping these sections is highly political and their justifications center around: 1) a semantic debate on the definition of “energy efficiency” and what should even be in IECC code; and 2) Preemption, which we introduced above.

The semantic debate boils down to a facially vapid and staggeringly self-interested idea from the Gas industry that “energy efficiency” and reducing Greenhouse Gas (GHG) are separate things, and that while the IECC code's purview is certainly improving energy efficiency, it is certainly not to reduce greenhouse gas emissions while doing so. As we've covered , and has been well researched , heat pumps, other electric appliances, and electric cars are more energy efficient than their fossil fuel alternatives in virtually every situation and no matter which way you try and define “energy efficiency” (BTU/watt, COP, HSPF2, etc).  Heat pumps' and induction stoves' advantages comes from physics itself, so arguments against them being more energy efficiency require discrediting science itself. Electric cars, too, are more efficient than gas cars, no matter how dirty the electric grid in your state. So the fact that the ICC Board sided with the gas industry on this – even with no alternative definition of “energy efficiency” offered – over the expertise and advice of their own professional staff, their appeals board, their Consensus Committees, and physics is incredibly discrediting and concerning for the ICC itself. According to some policy experts I heard discuss the matter first hand, ICC's Board likely did this out of a fear of going through an expensive lawsuit from these interest groups (an extremely well funded but dying industry group likely sees intimidation as their only strength right now), vs actually believing the arguments on the merits. I hope the policy experts who actually created the previously adopted code (and consensus that led to that adoption) get the message that the ICC acts on such threats, as they too can threaten suit. 

Meanwhile, the Preemption concern, brought in AHRI's appeal, is equally concerning and shows the chilling effect of the Ninth Circuit ruling referenced above; and again, it shows how well-funded appellants can use fear of legal action to thwart good policy. AHRI's “concern,” and therefore the ICC Board's concern, was that any code that rewarded builders for using heat pumps over conventional heating equipment could run afoul of the same federal EPCA law that also addresses the efficiency of appliances (the one that sunk Berkeley's efforts). Again, the federal government itself doesn't see codes like these as in conflict – they do not allow for less efficient appliances than the EPCA allows – but since a Circuit court has ruled on it (in a way that only effects their geographical jurisdiction) the ICC Board made the calculation that helping municipalities avoid a suit from these industries if they adopted the code from ICC's books somehow protected ICC reputation more than simply following the work of experts would.

Why it Matters

There are at least two way of considering the impacts of these decisions: 1) what this means for the future of ICC codes and the code-making process; and 2) what this means in practical terms around the progress we make creating a more energy efficient “built environment” – progress both generally and specifically around heat pump adoption.

Effect on the ICC Process

ICC is the incumbent code-originating body, and it's not going anywhere: code will continue to be generated and then adopted by states and local governments. Within institutions like the ICC, we (society) need to continue to have experts participating in the code creating process, even at the risk of disillusionment from weeks like committee members just experienced. While some of the most important efficiency codes got trashed, many new ones remained. Sadly, there will be some participants – and staff – who look at how the ICC Board operated and reasonably decide that they are not valued and should leave. Participants from anti-efficiency industries, however, are emboldened and will remain in, gaining voice-share in the code-making process and using the process for the good of their shareholders instead of the greater good. The gas and HVAC industry clearly want to slow the pace of innovation and change, and at some level this could happen, unless policy groups and experts somehow double down and recommit themselves to the process, including looking for ways to join the ICC Board of Directors and becoming an equally fearful lobby.

Practical Impact on the Built Environment

These weakened codes will also ensure we have a less energy efficient, and less healthy, built environment for decades to come. Most of the code changes impacted only how we build new structures; but new structures – while a small percentage of overall stock – are of critical importance.

Importance of New Homes

Most housing stock is not new (see the above graphic from the National Association of Home Builders ), but all housing stock was once new, of course, and – definitionally – still have some significant elements in place that were the standards at the time of being built. If you, like me, have owned a home from the 1940s possibly you still are getting the old knob and tube out of your system; or if you, like me now, own a home from the 1970s, perhaps you're still dealing with thin R12 insulation or a weird split panel 100 amp circuit breaker that can't handle additional electrical load when you need to replace a hot water heater) .

Also, while new housing is a small percentage of inventory it's a large percentage of industry . Home repair and renovation is dominated by smaller contractors (aka “mom & pops”) – folks who are harder to corral into trade groups and policy think tanks – while home building is mostly done by large, sometimes national or publicly traded, companies who are well practiced (and funded) at wielding their power.

New home builders are also the most misaligned stakeholders with actual homeowners and their communities, wanting to sell homes at the lowest price and then move on to new projects and fresh consumers. While we buy cars thinking about reliability and total cost of ownership, it's not nearly as common for folks to consider the cost of technical upgrades they will need to make in order to have a modern home in the future.

But for the homeowner there is a huge financial incentive for builders to use the best available technology and codes, as installing an EV charger or upgrading coolant lines or ducts can be insanely expensive after the home is built, but only marginally more expensive while it's being built. In addition, lumping the cost of these upgrades into the total mortgage value of a home can make these upgrades at the point of construction highly affordable, but trying to finance the upgrades later on a built and purchased home wildly unaffordable.

So the codes/standard for new homes are really important to get right, as they will dictate our built environment for the next 50 - 100 years.

Impact on Heat Pump Adoption

There are a number of dynamics that may be slowing the pace of heat pump adoption, but all can likely be solved over time by ramping demand.

For instance, we hear anecdotally that HVAC installers and plumbers at times shy away from or even dissuade consumers from buying heat pump appliances. Why? Some hypothesize it is simply a matter of comfort and education with the new technology that perhaps makes projects less profitable while they learn. If this is true, then any code that encourages adoption will also encourage the industry to get more comfortable more quickly, benefiting all buyers - not just buyers of new homes and commercial structures. But leave a gap for appliances to remain less efficient, or in the technological dark ages without Demand Response features, and these installers will stay in their comfort zone.

While heat pumps practically always save owners money in the long-run, the equipment can be more expensive up front, impacting demand. Part of this cost might be due to bi-directional heat pumps being more complex (e.g. need to heat and cool; and need for outdoor condensing units to incorporate defrosting features), but here the “learning curve” is also blamed for increased installation cost. Both aspects can likely get a lot cheaper with increased demand, even if the equipment stays modestly more expensive.

There is also a hypothesis that the supply chain for heat pump appliances has been less robust in the face of supply chain adversity than conventional HVAC equipment, impacting both demand from consumers (I need a new hot water heater now) and installer participation (wanting to make the sale now, not when the equipment gets in next month). Again here, there's nothing increased demand cannot fix, forcing manufacturers to prioritize makes/models required to meet the minimum codes required by bulk-purchasing new home builders.

Just as a HUD decision can impact the standards for more new homes than they originate loans for, all efficiency standards for new homes can impact the existing home market as well. As with any market transformation, the sooner we can align the right policy with the right solutions, the faster we can move forward.

What We Can Do

Accelerating the adoption of energy efficiency best practices generally and heat pumps specifically is critical for the health of the planet and its species, including humans.

With regards to this topic of ICC codes, it appears the most important thing anyone can do is to get active in your local community by understanding how your state and local government has historically adopted new code and then organize and advocate to improve that process to use both the most up-to-date code as well as to use new codes improperly booted to the Appendix.

Having conversations about codes with your councilperson or county executive might sound intimidating, but resources like ACEEE and IMT referenced above, as well as organizations like the New Building Institute , Clean Energy Works , RMI , EV Charging for All , SWEEP and MEEA can all provide data and resources to help you feel more confident as you start your local lobbying effort. Remember that your councilperson likely isn't an expert either – and likely isn't as captured by industry as a lawmaker at the state or federal level – so you have a real chance of having a real conversation at the level of government that matters most. In my experience, if you are just a concerned citizen, vs being associated with one of these groups or industry, you can often have a much greater impact on a per interaction basis, as good elected officials put up their guard more when someone has a professional reason to be in their ear, vs a purely civic but well researched reason.

While setting in place the right code for the entirety of a jurisdiction is most important, it is also important to make sure your city uses the best standards for its own building projects. Governments are often the largest buyers and builders in a given area, and beyond the ecological benefits, there can be a significant economic benefit to the entire area when a large buyer, like a city, forces the up-leveling of skills from its vendors. By using its own buying power to seed skill development, it can make sure any labor costs associated with using higher standards are front-ended by the government and come out lower for private buyers.

Longer term, it can also be important for your municipality to exercise its ICC voting powers in a way that aligns with your city's interests for a cleaner, more energy efficient future.

Lastly, as home buyers and business owners, we can also continue to use the power of our purse to make sure we are exceeding base efficiency standards, especially if we have the means to incur the higher up front costs, benefiting from cost savings long-term.


If you've made it this far, you - like me - have found yourself far more interested in codes than you were a week ago, and hopefully better understanding how they are made, the ways they can get weakened, how that impacts our built environment, and what are can do about it. My personal action from this will be to engage with my councilperson here in Baltimore, who has been responsive to some of my other contacts regarding EV policy. Meanwhile, for Heat Pump Review , I plan on spending more time exploring how these codes impact heat pump trends and adoption and will report back here as I learn more.

Nate Westheimer
Nate Westheimer Editor, Heat Pump Review
Nate Westheimer is the Editor of Heat Pump Review. He as worked in the tech industry for nearly 20 years, including as a Director of Technical Product Management at Amazon, the CEO of Picturelife, and as the Executive Director of the NY Tech Alliance.
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