
💼 Briefcase: Making Academia Look Cool Since...Now
briefcase | invest smarter | Issue #142
🥸 Nerding Out On Housing
A few weeks ago, the housing brainiacs over at the Office of Policy Development and Research (PD&R) of the U.S. Department of Housing and Urban Development published an entire academic journal issue on the topic of zoning reform.
Sexy right?
And it’s a juicy report!

Now, before closing the blinds on us, we read the entire thing so you don’t have to…All 341 pages.
So now you can impress your friends as if you read the entire thing; that’s the power of briefcase!
🥸 ADUs: Hide and Seek Champions
The first article we look at is titled Where Will Accessory Dwelling Units Sprout Up When a State Lets Them Grow? Evidence From California. It’s all about the effect that liberalizing accessory dwelling rules in California had on the housing supply.
Key Finding: ADUs, often tucked away hiding from prying eyes, might just be the ninja warriors we need to sneak in some extra housing without causing a neighborhood riot. Some may even say, they’re ADUseful 😉😉.
Since 2016, California has enacted several laws to promote the development of ADUs. This research evaluates ADU permitting in California's Bay Area and Southern California, leveraging state-collected data.
The study found that ADUs account for a significant portion of recent housing permits and are often located in areas with better job access. The authors argue that these findings can guide state and local governments to understand potential ADU development areas after ADU regulatory liberalization.
🥸 Zoning in on Rezoning
The second article we’ll look at is titled California’s Strengthened Housing Element Law: Early Evidence on Higher Housing Targets and Rezoning. But we think a snappier title is Rezoning Rodeo: California's Bold Blueprint for a Housing Hoedown. Oh well, their loss.
The authors go deep into the revamped housing planning system in California, spotlighting its significance in land use reform impacts and intergovernmental clashes concerning housing policy.
For the first time in half a century, the state's mandate for planning set housing targets for the 2021-2029 planning period, surpassing the zoned capacity for new housing in numerous municipalities.
Key Finding: Focusing predominantly on the 209 municipalities in Southern California, it was observed that these cities, representing under one-third of the state's populace, pledged to over a tenfold increase in rezoning compared to the prior planning period in 2014.
Looks like when you’re forced to meet housing targets, the main tool cities move to is rezoning. Let the builders build!
🥸 Capital Housing Gains
D.C. isn't just about politics. Between 2000 and 2020, it had a housing glow-up, increasing its stock by a cool 15%.
Does Housing Growth in Washington, D.C., Reflect Land Use Policy Changes discusses this trend, finding that most of the development that contributed to the increase in housing occurred where there wasn’t single-family zoning.
Single and Ready to... Stay That Way? should have been the title of this one.

🥸 Zoning Zen: Ramapo, NY
Ramapo didn't just dabble in zoning reform—they went all-in, showing that even sleepy suburbs can get funky with housing. Learning from Land Use Reforms: The Case of Ramapo, New York explores the history and implications of land use reforms in the suburban town of Ramapo, New York.
While many regions are currently amending zoning regulations to promote housing, especially "missing middle housing," Ramapo's efforts to loosen development rules span nearly four decades.
The Ramapo case reveals that introducing multifamily zoning—even in established suburban neighborhoods—can propel the production of many new housing units. In contrast, they find that regulations that only permit accessory units yield more restricted outcomes.
Key Finding: Targeting smaller multifamily builds with zoning reforms seems to be the scalpal other metros may need to increase housing supply.
🥸 The Strings Attached Dilemma
Finally, let’s look closer at Upzoning With Strings Attached: Evidence From Seattle’s Affordable Housing Mandate.
This article dissects the effects of a significant municipal residential land use reform on new housing construction and the behavior of developers. It delves into Seattle's Mandatory Housing Affordability (MHA) program, which introduced lenient zoning regulations while simultaneously mandating affordable housing construction across 33 neighborhoods in 2017 and 2019.
While these reforms facilitated denser development ("upzoning"), they also mandated developers to either allocate a portion of their project units at below-market rates or contribute to a citywide affordable housing fund.
Through some academic wizardry and formulas we’ve never heard of, the authors demonstrate that new construction declined in the upzoned regions with affordability stipulations. Unsurprisingly, developers strategically positioned their projects away from MHA-designated areas, gravitating towards nearby zones exempt from the program's affordability conditions.
Key Finding: Other incentives are needed to promote affordable housing projects. Developers are businesses, and if you cut their bottom line by forcing them to build below-market rental units, they simply won’t build.
So What? Academic Avengers came out in full force on this one, providing a number of key takeaways that we have been talking about for a while at briefcase.
Mainly, single-family zoning limits supply, missing middle multifamily is the bee’s knees, and mandating developers to build certain types of units is a losing battle.