A new working paper adds another perspective to the debate about easing zoning regulations to address the affordable housing crisis.

Nolan Gray writes that new research from Evan Mast of the W.E. Upjohn Institute for Employment Research offers empirical evidence of the longer-term effects of upzoning on housing affordability. The working paper provides new insight into the robust debate, including Richard Florida’s look at a recent paper by Andrés Rodríguez-Pose and Michael Storper.
Mast’s research takes a closer look at filtering, the process by which newer housing frees up older, less expensive housing. His analysis of housing data from 12 U.S. cities includes tracing back household moves, what he calls a "migration chain," says Gray:
His model suggests that for every 100 luxury units built in wealthier neighborhoods, as many as 48 households in moderate-income neighborhoods are able to move into housing that better suits their needs, vacating an existing unit in the process. Somewhere between 10 and 20 of these households are coming from among the city’s lowest-income neighborhoods, vacating units and reducing demand where housing is most likely to be affordable for working families.
While Gray notes that the upzoning debate is far from resolved, these findings could play an important role in developing strategies and policies to tackle the affordable housing problem. "For starters, the case against allowing new market-rate housing in high-income neighborhoods would be considerably weakened. And, as Daniel Herriges points out over on Strong Towns, it could also call into question well-meaning policies that suppress the construction of new housing, such as inclusionary zoning."
FULL STORY: How Luxury Units Turn Into Affordable Housing

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City of Albany
UCLA Lewis Center for Regional Policy Studies
Mpact (formerly Rail~Volution)
Chaddick Institute at DePaul University
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Great Falls Development Authority, Inc.
HUDs Office of Policy Development and Research