By Muhammad Hani Ahsan, Katie Farrell, Dian Gu, and Huda Mehdi Shah
Edited by: Annika McGraw
Graphic by: Norie Wright and Ava Lagressa
There are 124 million residential and 5.9 million commercial buildings in the United States.1 Buildings are energy intensive, produce greenhouse gases, and impact the natural environment significantly. In the United States, buildings account for about 40% of total energy consumption and around 30% of energy-related CO2 emissions.2 Moreover, buildings account for over 12% of water use, 65% of all waste outputs, and 70% of electricity consumption.3 Buildings in large cities use more energy than industry and transportation accounting for 50–75% of total energy use.4 As a result, there is growing interest nationally and in many states in policies to make buildings more energy-efficient, sustainable, and green. Building codes are seen as an effective policy tool to conserve energy and other resources and reduce the environmental impacts of buildings.
Green building codes target areas of traditional building codes that have the potential for sustainability, including site selection, water conservation, energy efficiency, renewables, indoor environmental quality, and resource conservation. These codes can have a major impact on energy use and emissions but adoption throughout the United States is lagging due to several challenges. This paper explores the challenges facing building codes to argue that the Federal government funding and coordination through the Environmental Protection Agency can enable the adoption of effective green building strategies including electrification and retrofitting.
Limited Adoption of Green Building Codes in the United States
Parts of the United States, such as California, New York, and major cities in Colorado, have made significant progress in making buildings sustainable. Using building codes, these jurisdictions are promoting electrification, insulation, solar mandates, EV charging, and other innovative strategies. However, most places need more modern, energy-efficient, and sustainable building codes. A Federal Emergency Management Agency (FEMA) study on disaster resilience in building codes found that 65% of counties, cities, and towns across the United States needed modern building codes.5 Up to 39 states are in the lowest rank with less than 25% of communities having updated building codes.6 Data about green building code adoption is more difficult to find as there is no federal agency collecting data on all states. We used the American Council for Energy Efficient Economy’s (ACEEE) scorecard to understand the adoption of green building codes in the United States. The analysis for states revealed that most states lag in the adoption of building codes. The average score was 3.95, and 28 states scored below the average. The pie chart demonstrates that more than 75% of states have a score of 6 or lower, meaning these states got half or less than half the points.
Figure 1: Pie Chart Depicting Proportion of Scores by Building Code Ranges7
Analysis of building policy scores reveals that most cities, using data on cities from ACEEE, also need to catch up in efficiency energy codes for buildings. Out of 30, the average score was 9.03. Sixty-nine cities scored below the average, and the vast majority have a score lower than 10. Based on the analysis, most cities needed help adopting energy codes, enforcing energy codes, targeting old buildings, and other initiatives.9
Figure 2: Pie Chart Depicting Proportion of Scores by Building Code Ranges8
Factors Affecting Building Code Adoption
Federalism and Federal Law
The federal government cannot mandate states and other jurisdictions to adopt a green building code, nor can the federal government require a standardized code for all jurisdictions. Building codes are the mandate of states and local governments, and the role of local governments is especially crucial in states where there is no statewide code. Therefore, uniform adoption of building codes, let alone energy or green codes, is challenging. Due to a divided Congress, any national mandates or progress toward federal requirements for building codes now and in the future are unlikely.10 In some cases, federal law can limit state action. Many states and cities, like Berkley and Houston, attempted to adopt building codes dubbed ‘gas bans.’ These laws require most, if not all, infrastructure and appliances in new buildings to be all-electric with electric cooking, heating, drying, and EV charging. However, the Energy Policy and Conservation Act (EPCA) preempts state and local governments from setting standards concerning energy efficiency, energy use, or water use of products regulated by EPCA including cooking and drying.11 The federal preemption led the Federal 9th Circuit Court in California to strike down Berkley’s all-electric building codes and may affect similar laws in other states. However, the law does not explicitly state that jurisdictions cannot regulate cooking or drying to benefit health and well-being and reduce carbon emissions. The decision is based on the interpretation of the law upheld by the 9th Circuit Court.12 Therefore, reforming EPCA to allow states to require voluntary or mandatory electrification of cooking and drying can clear the gridlock many state and local governments face in adopting green building codes and technology.
National Level Codes Lag Behind Climate Action
Jurisdictions usually adopt existing building standards and apply them to their communities. Building standards specify design requirements for many different elements of buildings, such as energy or sewage, and serve as the building blocks for model codes.13 Model codes are off-the-shelf building codes that governments can adopt.14 The International Code Council is the primary national-level developer of model codes. It publishes a family of 15 model building codes called the International Building Codes including the International Green Construction Code (IgCC) and the International Energy Conservation Code (IECC). The IgCC provides design and construction provisions for buildings with integrated energy and water efficiency, site and material sustainability, land use, and indoor environmental quality while the IECC primarily focuses on energy efficiency. Since most jurisdictions in America use the ICC’s codes, these codes must stay up to date with the developments in states and the latest innovations in science and technology. There are concerns that the ICC’s code lacks climate action and preparedness now and may remain outdated.15 The ICC’s code does not have voluntary electrification requirements and mandatory electrification provisions are highly unlikely. The code does not mandate efficient technologies such as heat pumps, solar panels, EV charging, and other innovative strategies adopted by many states and cities. A Government Accountability Office study on disaster-resilient building codes found that model code-developing organizations including the ICC often lack forward-looking climate information due to technical and institutional barriers.16 Therefore, these organizations produce codes that are not up to date with innovative technologies and practices17, recommending the need for federal government efforts to coordinate and share information with these organizations for effective code development.
Lobbying and Resistance to Change
Lobbying and resistance to change from stakeholders affected by building codes, including the construction industry, oil, and gas, home builders, real estate, homebuyers, and other businesses, explain less advanced codes at the national level and state levels. Industry lobby groups, such as The National Association of Home Builders (NAHB) and the American Gas Association use public forums and the ICC’s public process to influence decision-making. After unprecedented participation by pro-climate groups in the development of the 2021 IECC draft, industry lobbying groups appealed and ultimately succeded in removing many voluntary electrification provisions.18 Beyond the public process, lobbying groups have used backchannels to influence the ICC’s decision-making. The NAHB was given 4 out of 11 seats on two technical committees in a secret deal that was concealed for years.19 Before the deal, the energy efficiency of building codes increased by 32% over six years compared to less than 3% over the following six years.20 Groups resisting green building codes can also use courts to halt action such as the Restaurant Association in California challenging Berkley’s building code in court. The ICC also decided to alter the process for developing the energy code giving more power to special interest groups. The IECC will not be developed by the public review consensus process followed for the other 14 codes in the IBC.21 This will eliminate the input of hundreds of pro-climate action groups and federal agencies, empowering a select few to through nomination to the ICC’s new Energy and Carbon Advisory Council.
Costs to Homeowners and Businesses
Green building requirements increase the construction and other upfront costs, increasing the prices of buildings, especially homes, and reducing sales. The NAHB argues that the additional up-front cost to build an all-electric house ranges from $3,832-$15,100 while the adoption of the 2021 IECC can add up to $31,000 to the price of a new home.22 While these technologies pay for themselves in the long run23, the upfront costs can anger stakeholders because people don’t see the benefits immediately. The NAHB estimates that for every $1,000 added to the cost of a home in this state, nearly 10,000 prospective homeowners are priced out of the market.24 The rise in the costs of constructing and operating a building and the effects on the market for real estate due to greener codes generate opposition to the green building movement. Other sources of opposition include technical complexities in complying with codes, changing existing practices and associated costs, general opposition to regulations, and the role of the government.25
State Priorities
Decision-making at the state level about green building codes is influenced by political and economic priorities. Some states such as Texas are more interested in protecting the state’s oil and gas economy26, restricting local governments from adopting climate-friendly policies. Texas legislated a preemption policy that limits local governments from adopting climate change policies beyond state law. The bill was adopted to restrict cities such as Houston and San Antonio from adopting building codes that limit gas infrastructure.27 Other states, including Arizona, Texas, Oklahoma, Tennessee, Kansas, and Louisiana, have since also adopted preemption laws. In many states such as Texas, lobbying by special interest groups also motivates governments to invest in green building and energy codes.
State and local governments are also concerned about the costs of adopting green building codes. Once a code is adopted, a jurisdiction has to spend money on “the extensive code review process, purchasing codebooks, staff, enforcement materials, and updating their compliance tools and training programs”.28 Many states and local jurisdictions cannot pay for the resources required to manage the building code adoption process.29 Regularly updating codes can also be expensive as the updating cycle costs money due to adoption costs but also because new provisions require training of staff and officials as well.
The labor shortage is another challenge. Many states and local governments need help finding qualified staff to manage their code adoption process. Positions are unlikely to be filled in the coming years because of small building department sizes, inconsistent salaries, and the growing building science knowledge needed for an increasing list of responsibilities under each new iteration of the codes.30 The skilled labor problem will likely worsen as the ICC estimates that 80% of building code professionals retire in the next 15 years.31 The issue of funding is acute in smaller jurisdictions as some officials say they “lack the funding or personnel to staff a building code enforcement office”.32
The Role of the Federal Government
Funding
The federal government can promote green building codes through funding for jurisdictions, businesses and individuals, and human capital development. The Infrastructure Investment and Jobs Act (IIJA) allocates $225 million for energy code implementation through the Resilient and Efficient Codes Implementation (RECI) program.33 The Inflation Reduction Act (IRA) makes $1 billion available for technical assistance including $330 million for adopting the 2021 IECC and $670 million for meeting or exceeding the zero energy provisions in the IECC.34 While funding can subsidize the costs incurred by jurisdictions due to code adoption and enforcement, these programs can be improved by targeted funding for cities and states that have the weakest building codes. The federal government is also incentivizing individuals and businesses through tax incentives including the Residential Renewable Energy Tax Credit, the Energy-Efficient Commercial Building Deduction, and the Federal Tax Credit for New Energy-Efficient Homes.35 By targeting people and firms, the government can reduce the opposition to green building codes from organized industry and consumer groups. Financial incentives can also motivate homeowners and firms to adopt green building practices even in places with lax codes. Incentives for individuals and businesses must be targeted at low-income families and small businesses to ensure an equitable transition to sustainable buildings. Finally, the federal government should establish a funding program for the training and education of a new generation of code developers, researchers, enforcers, and reviewers to lead the transition to green buildings and address the labor shortages.
A Federal Agency Tasked with Promoting Green Building Codes
The federal government launched the National Building Code Initiative aimed at promoting disaster-resilient codes. FEMA is the leading federal agency involved in disaster resilience in buildings, spearheading the Building Codes strategy, managing the Building Code Adoption Tracking, and publishing data on best practices for building codes.36 However, there is no federal agency that is focused on green building codes. We argue that the Environmental Protection Agency (EPA), in consultation with the Department of Housing and Urban Development, the Department of Energy, and relevant state agencies, should be tasked with carrying out efforts to promote green building codes nationwide. The agency is suited for the task as it works on promoting a healthy and sustainable environment and buildings not only consume significant resources but also produce externalities on the environment. The EPA also already carries out some work on sustainable buildings including publishing a policy toolkit for building performance standards to help decision-makers.37
Following the GAO’s advice for disaster-resilient building codes38, we argue that the EPA can take the lead in promoting green building and energy codes by collecting and publishing data on building code adoption and enforcement including a tracker. This data can help identify areas that lag behind the rest of the nation and enable effective targeting of funding and expertise from the federal government. We also argue that the EPA should convene federal agencies for a governmentwide effort to provide the best available forward-looking climate information to standards-setting and model code organizations for consideration in the development of design standards, building codes, and voluntary certifications. Several sources of information related to green building codes exist. Many states and local jurisdictions have more advanced building codes and many organizations, researchers, and federal agencies produce data and information related to green buildings. The EPA can coordinate this data and share it with national standards and codes organizations to ensure updated building codes.
Green Building Strategies
We argue that the federal government, the EPA, and code-developing organizations, should prioritize the electrification of buildings, and retrofitting of old buildings as these strategies can reduce energy use and emissions while being cost-effective, especially in the longer run. Electrification refers to converting buildings to electric appliances rather than natural gas or fossil fuels. Major elements of a building that should be electrified include space and water heating, cooking, electric vehicle charging, drying, lighting, and air conditioning. Specific building technologies driving electrification include air source heat pumps, geothermal heat pumps, induction cooktops/stoves, high-efficiency electric or heat pumps, and water heaters. While these technologies use electricity to decarbonize buildings, renewable electricity generation must be integrated into residential and commercial buildings. Solar panel mandates for including solar panels or solar panel space on rooftops can help generate renewable energy to power green technologies. The progress toward electrification of buildings nationwide will take time. However, the first step in the transition is voluntary electrification requirements similar to the ones that the ICC decided to remove from the 2021 IECC. These requirements can enable the transition to electric buildings in the future as buildings will include infrastructure that can enable the use of electric appliances now or retrofitting in the future.
The benefits of electrification are immense in terms of costs and emissions. Switching to efficient electric heating systems and appliances powered by pollution-free electricity could cut United States carbon emissions by 1 billion tons annually.39 California’s energy code and CalGreen will save Californians $1.5 billion in costs and 10 million metric tons of greenhouse gas emissions over the 30-year life of the buildings.40 Compared with gas-fueled single-family homes, full electrification can reduce greenhouse gas emissions in single-family homes by 30% to 60% in California. As the carbon intensity of the grid decreases, the savings will increase from about 80% to 90% by 2050.41 It is vital to begin the transition now and ensure that buildings built today can adapt to the technological and policy advancements of tomorrow.
Since most buildings in use in 2050 are already built, retrofitting is essential to ensure a green transition of buildings.42 Additionally, most emissions come from existing buildings rather than creating new ones. Buildings are designed to last around fifty years unless proper maintenance ensures continued survival and usage.43 Retrofitting, the idea of taking older buildings and reforming their infrastructure to make them more inhabitable and, in this case, sustainable, is a longstanding yet underutilized tactic for solving issues surrounding energy use, land preservation, pollution, overcrowding, and urban heat. The United States is more prone to bulldozing old buildings, creating new ones, or using natural habitats to generate new income. However, we contend that retrofitting is a cost-effective strategy that code developers and all levels of government should consider due to its immense benefits.
Retrofitting modernizes older buildings to make them more efficient and sustainable44 by decreasing energy consumption, as utilizing retrofitting tactics can offer yearly energy and emissions savings of 4% and 3.9%, respectively.45 Additionally, it can reduce a home’s energy usage by 58% to 79% and its emissions by 32% to 56%.46 The average structure is designed to last around fifty years, but retrofitting can increase a building’s life span anywhere between 30-50 years.47 Thus, it can reduce community dependency on the construction of new buildings, simultaneously increasing sustainability and preserving natural land.48
To promote retrofitting, governments should consider retrofitting existing structures while also building new structures that are easier to retrofit in the future by encouraging infrastructure that can accommodate electric appliances in the future. Some cost-effective retrofitting strategies include focusing on updating older buildings with proper insulation in warmer and cooler climates to prevent energy loss. This can include upgrading HVAC units to make them more durable and sustainable, improving a building’s envelope to protect against harsh weather, and turning towards renewable energy sources to power a building. Retrofitting should also include changing the layout of roofs by either mandating white building roofs or creating roof gardens. White roofs allow for the albedo effect (the reflection of the heat off lighter-colored surfaces) to take place.
Conclusion
This paper has demonstrated that while building codes lag in the United States, the federal government can play a key role by subsidizing the costs of governments, homeowners, and businesses. Through the EPA, the federal government can manage the collection and dissemination of up-to-date data on green building codes and technologies including sharing it with the national level code developers to ensure forward-looking building codes. Finally, the effective strategies that the federal government can promote are the electrification of new buildings and retrofitting of buildings to ensure sustainability, reduce energy use, and minimize emissions.
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