Parking Reform Legalized Most of the New Homes in Buffalo and Seattle

Studies from two very different cities showed the same result.
What comes after repealing parking mandates? Lots of newly legal homes. Studies from two cities observed that in the years following reform, 60 to 70 percent of new homes would previously have been illegal to build.
The new data add to the heap of evidence that parking mandates---local rules that ban new homes and businesses unless they have a pre-determined number of off-street parking spaces---are a binding constraint on housing construction. While only a few buildings opted out of providing parking entirely, most new homes in the studies ultimately benefited from the increased flexibility.
“It isn’t surprising,”
said researcher C. J. Gabbe, who authored one of the studies. According to Gabbe, homebuilders have been saying for a long time that demand for off-street parking was lower than what zoning rules required.
The results suggest that across jurisdictions, the majority of potential future homes are being held back, in part, by parking mandates. Based on little to no data, these requirements limit the number of homes that can be built and increase costs for the ones that are, contributing to a housing shortage that has been decades in the making.
“Cities of all types stand to benefit from undoing constraining parking policies of the past,” researchers from Buffalo wrote in their findings. In many cities, though, these new homes remain illegal to build.
Two different cities: Seattle vs. Buffalo
It’s hard to imagine two housing markets more different than Buffalo, New York, and Seattle, Washington. Seventy years of depopulation and disinvestment have left Buffalo with the oldest housing stock in the United States, with most homes pre-dating World War II. Here, housing affordability hinges as much on the high rate of poverty as a shortage of housing. Reusing derelict historic buildings and vacant lots was a primary goal of Buffalo’s zoning code overhaul in 2017, which eliminated parking mandates citywide.
Seattle, by contrast, has never been bigger. Since 2010, the population has increased 21 percent. Despite a surge in homebuilding (one in every three homes was built in the past twenty years), population growth continues to outpace construction, creating intense competition and escalating prices. Partway through this building boom, in 2012, the city reduced or eliminated parking requirements in urban centers and near frequent transit stations.
Both of these cities’ policy changes provided a natural experiment for measuring the effects of parking policy. Researchers in Buffalo collected information on 36 major developments that went through permitting in the two years after its so-called Green Code was adopted. In Seattle, a different team of researchers collected data on 868 new multifamily buildings permitted from 2012 to 2017, accounting for over 60,000 new homes.
Sightline asked both research teams to look through their numbers to see how many homes were in buildings that would have been illegal before the reforms. Both datasets yielded a strikingly similar answer: more than half of new homes.
Lifting parking mandates supported already growing construction rates
The timing of Seattle’s parking reform coincided with an increase in multifamily construction nationally, as the United States recovered from the late aughts’ Great Recession. Similarly, at the time when Buffalo eliminated parking minimums in 2017, people were already talking about Buffalo’s renaissance. New census data confirmed the city is growing again for the first time in 70 years and seeing a record amount of new investment.
“It’s impossible, really, to tie a specific code change to changes in the market,”
explained Brennan Staley, a strategic advisor for Seattle’s Office of Planning and Community Development. Other local regulations, housing prices, and international finance markets all play a part in the real estate market. Michael Hubner, who works on long range planning in Seattle, agree...