If communities want to seriously reduce their carbon emissions, they must reduce the amount of driving that people need (and want) to do. That means enacting zoning reform to allow for a range of housing units and typologies, incentivizing infill development, and updating excessive parking requirements. Critical emissions thresholds are already being crossed; To stave off even worse effects of climate change, the time for building climate-friendly communities is now.
Current zoning makes people release more carbon
In 2024, the global average temperature, for the first time, exceeded 1.5°C above pre-industrial levels (the target established in the Paris Agreement), largely due to greenhouse gas emissions from the burning of fossil fuels. These emissions fuel climate disasters that have harmed communities across the country. Floods, wildfires, hurricanes, and droughts impact every corner of the U.S., causing hundreds of billions of dollars in damage; as global temperatures continue to rise, these events are only set to become more common and more intense.
Much of the efforts to reduce carbon emissions and prevent more severe climate impacts have focused on transitioning to less carbon-intensive electricity sources, like solar, wind, and nuclear. Equally important are efforts to reduce emissions from transportation, which, since 2017, have consistently exceeded those from electricity generation. Passenger cars and light-duty trucks (like SUVs, minivans, and pickup trucks) together accounted for 57 percent of U.S. transportation emissions in 2022, primarily due to a 47 percent increase in vehicle miles traveled since 1990. And while transitioning to electric vehicles can and should be an important part of reducing transportation emissions, the majority of cars on the road are projected to still be gas-powered in 2050.
One of the most effective (and most overlooked) ways to reduce transportation emissions is to reform their zoning and land use policies. Current policies tend to separate uses, keeping jobs and amenities away from residences while also dedicating large swaths of land to low-density, detached single-family homes. This forces people to drive more, preventing those who may be interested in living less carbon-intensive lifestyles from doing so.
Mixed-use communities, where residential, commercial, and other establishments are located close to one another, allow people to either drive shorter distances to reach their destinations or forgo driving entirely as they walk or roll to their workplace, the grocery store, a cafe, or any other amenity. As an added benefit, proximity to different amenities and needs also contributes to community cohesion and quality of life, supporting the independence of residents who can’t drive due to preference, age, or the costs of car ownership. And many housing types other than detached single-family homes, ranging from anywhere between duplexes to large apartment complexes, allow more people to live on a smaller footprint of land, so a growing population can be accommodated closer to amenities and not far away in the urban fringe, where driving long distances is most likely a daily fact of life. Where mixed-use buildings and a diversity of housing types do occur, usually in downtowns, household carbon emissions are far below the national average, thanks to reduced car dependency, less carbon released from construction for buildings and infrastructure, and the increased energy efficiency of housing types that share walls between units.
To reduce carbon emissions, communities must prioritize the development of more areas where uses are mixed and a variety of housing types coexist. Right now, around 75 percent of residential land in many American cities is zoned to only permit detached single-family homes. This is not to mention other zoning tools, like parking minimums, that can further constrain the development of other types of housing. Unless communities rethink their land use policies, zoning that mandates detached single-family homes everywhere will continue to hamstring efforts to reduce carbon emissions.
Reducing emissions with zoning reform
If local land use regulations allow for a less carbon-intensive built environment, emissions could drop by up to 70 million tons per year. Combined with other sustainability efforts, these efforts could significantly reduce the U.S.’s climate footprint. Communities that allow for more people to access their daily destinations with less driving, by relaxing or rescinding their bans on non-single-family housing types in most residential areas, are already seeing the benefits of developing in a more climate-friendly way.
In Minneapolis, the Minneapolis 2040 plan allowed for more apartments to be built along commercial corridors and near transit, rescinded the ban on duplexes and triplexes on residential lots in more than half of the city, and eliminated unnecessary parking requirements. Between 2017 and 2022, the city experienced rapid growth in its housing stock (triple the average rate for Minnesota), with only three percent of newly-constructed housing units being single-family homes. Between 2017 and 2021, transportation emissions in Minneapolis declined by over 18 percent, compared to two percent nationally.
Similarly, since 2019, the state of Oregon has allowed for duplexes, triplexes, cottage clusters, and other housing types to be built in its cities and towns while also getting rid of unnecessary parking requirements. The impact of this legislation has been limited thus far by the need to update local regulations; however, in Portland, which updated regulations in 2021, 1,400 ADUs and missing middle housing units have been built in formerly single-family only zones. Oregon transportation emissions, since 2019, have declined by 5.5 percent, compared to under four percent nationally.
Many other efforts to reform zoning codes, led by cities and states from across the country, have also been completed or are underway, often as part of initiatives to address the rising costs of housing. However, significant zoning barriers to affordable housing (and to more climate-friendly communities) remain, including potential opposition from community residents, developers, or businesses that may be wary of the changes. For communities working to reduce emissions, zoning reform, paired with equitable community engagement strategies, will be crucial.
In spite of the challenges, communities can take action to mitigate the effects of climate change. Creating a built environment that is more climate resilient will require bold action from elected officials, community leaders, and residents alike. Community leaders and residents should make efforts to ensure their needs are reflected in land use policies by contacting their local elected officials or by participating in community outreach regarding built environment topics. However, as the ones with the greatest ability to shape conservations on these topics, elected officials and others in local government, must lead the way. Reforming land use and zoning policies must become a priority for local and state governments—not just to alleviate the housing crisis or to reduce inequities, but also to reduce emissions, creating greener communities for all.