Blog Climate Policy

Housing Policy Is (Still) Climate Policy

April 23, 2024

An abundance of climate and urban planning research has shown that urban sprawl is responsible for a significant share of global climate pollution. Sprawl requires longer trips in private vehicles, measured in “vehicle miles traveled,” or VMT. It also increases “embodied” carbon in the built environment, through the use of more building, infrastructure, and related materials; it increases building energy use; and it consumes undeveloped lands that often serve as natural carbon sinks.

In “Why State Land Use Reform Should Be a Priority Climate Lever for America,” Rocky Mountain Institute researchers analyze what effect shifting new housing development away from sprawl, and concentrating new homes in dense, low-VMT areas might have on climate pollution, finding a variety of positive effects.

Key Takeaways

  • State-level land use reform to encourage compact development can reduce pollution by 70 million tons of carbon dioxide annually by 2033.
  • Such reform would have a greater effect than 60 percent of the country adopting California’s 100 percent zero emission passenger vehicle goal by 2035.
  • Half the emissions reduction would come from reduced vehicle travel, a third would come from reduced vehicle manufacturing, and the remainder would come from the preservation of natural carbon sinks and the construction of more-efficient buildings.

The researchers’ methodology used population growth forecasts and housing underproduction data from Up For Growth to optimistically project new housing construction totaling 13 million new units nationwide by 2033, then combined that with census block level VMT data to estimate transportation emissions under two different development scenarios: “business as usual” (BAU) and “low VMT, compact development.”

The BAU case assumes that new housing is added in such a way that per-capita VMT remains roughly the same. The low-VMT case, on the other hand, assumes that 90 percent of new housing is built in compact development in 90th percentile low-VMT areas in each state. In both cases, the VMT per capita for existing housing remained unchanged.

They then consider three sources of greenhouse gas (GHG) emission reduction from land use policy change: direct GHG savings from VMT reductions (accounting for electric vehicle use); vehicle lifecycle GHG savings; and GHG reduction from other non-transportation sectors like building energy use, building materials, and the destruction of natural carbon sinks by urban sprawl.

They find that reduced VMT from land use reform would, on its own, reduce GHG emissions by 31 million tons of CO2 per year by 2033. When combined with vehicle lifecycle savings and non-transportation effects, land use reform would reduce GHG emissions by 70 million tons of CO2 per year. Further, concentrating new housing in low-VMT areas would allow the residents of that new housing to drive 40 percent less than average for their states under the BAU scenario, and that states could see significant overall per capita VMT reductions.

Beyond reducing emissions, compact development would preserve natural carbon sinks, farmland, wetlands, grasslands, and forests that provide resilience against wildfires and floods. Concentrating new housing in dense multifamily developments would also reduce water consumption, a key goal here in California.