Thread by @jenny_schuetz

#HousingOpportunity Ingrid Ellen opens: NIMBYism from wealthy homeowners isn’t only opposition to new housing. Renters are also nervous that development drives up rents. What does evidence tell us?

Some supply skeptics argue that new development won’t bring down rents, others argue new housing will actually drive up rents. Let’s unpack the assumptions behind those arguments.

There’s lots of research on filtering: more tightly regulated housing markets see less downward filtering and more upward filtering. But we should be realistic about how long downward filtering takes.

Super important point: there’s an inherently limited supply of land in any given city/neighborhood. But land can be used more intensively, to allow more people to live in high opportunity places.

We don’t have much research on how upzoning impacts housing markets, in part because there aren’t many examples of upzoning. Will be super interesting to observe what happens in Minneapolis and Oregon over next few years!

Adding new market rate housing won’t meet needs of low income households. Upzoning must be paired with more subsidies. (So so important!)

Tsur Somerville hits key to resistance: people don’t like change in their neighborhoods. It’s not just about price impacts, it’s about people’s comfort with change.

Next up: Bob Ellickson presenting his new research on zoning in 3 markets: Silicon Valley, Austin TX, and New Haven CT. Great to have some data in less studied places!

Zoning maps!! Who else is excited?

Of land on which residential uses are permitted, 90% is reserved for single family. Yikes! (Denominators matter.)

Silicon Valley isn’t terrible on SF minimum lot size. New Haven metro requires mostly larger than quarter acre!

@EvanMast2 starts by reminding us that “housing affordability” is an often ambiguous term. We need to specify, affordable for whom (whomst).

How filtering works within housing markets depends partly on where new households come from. Moving in from another metro area? 2nd homes? Kids moving out of parents basement?

Evan has some very cool/creepy data: tracking origins of new households moving into newly built housing.

For 100 new market rate apartments, more than half of occupants are moving up from lower income neighborhoods within same metro area. That does free up housing in cheaper nhoods, which helps poorer renters.

Tsur Somerville reminds us that regulation that creates uncertainty, increases time to develop lowers the value of land to developers.

Moving to our international comparison: what happened when Vancouver BC legalized “laneway homes” (ADUs)?

These are some gorgeous ADUs! I’d live in one in a heartbeat.

Laneway home nearby decreases SF home values only in most expensive neighborhoods. (Which to me is actually a social benefit). Other than very rich, most people don’t mind laneway homes nearby.

@JedKolko dives right into tough question: how do academics measure strictness of land use regulations? (Hint: it’s really hard.)

Tsur: in Vancouver zoning is negotiable, so hard to measure “stringency”.

Also really hard to separate regulations from amenities (h/t @TomDavidoff ). High regulation places often have very high amenities.

Ingrid: benefits of more housing takes time to become apparent, costs may be felt upfront.

Bob Ellickson: people like stuff they’re familiar with. Example: big commercial signs along Minneapolis riverfront. (And of course, Boston Citgo sign.)

@EvanMast2 Midwest is less NIMBYish than coasts. (Me: yes!)

@neelkashkari asks: how did dense places become dense? Ingrid: they planned dense grid even before houses were built. Bob: also nyc grew mostly before zoning.

Tsur: Asian cities are very dense and grew recently. Governments often own more land and can direct growth more to fit public goals.

Morris Davis: is there role for federal govt in solving supply puzzle? Ingrid: we definitely need more federal subsidies for poor renters. Also declining mobility rates are concerning.

Great audience question: low income nhoods (esp nhoods of color) are very concerned about gentrification and displacement. How can Economics research address those concerns, taking them seriously?

Tsur: it’s not just about new housing, it’s also about new amenities. Having public parks, community centers, amenities for wide range of income is fairer than all private amenities.

Ok Gotta pause the live tweeting to moderate next panel...tune into webcast!