The housing crisis is simply a supply-and-demand problem

The claim

The housing crisis is fundamentally a supply problem. Housing costs are high in cities like San Francisco, New York, and Seattle because not enough homes were built to meet demand. The solution is straightforward: remove regulatory barriers to construction — exclusionary zoning, height limits, minimum parking requirements — and let the market build its way to affordability. Government attempts to control rents make things worse by discouraging new construction and reducing the supply they were meant to protect. The clearest international evidence comes from Tokyo, where permissive zoning has kept prices flat for decades.

The mechanism

The supply-demand claim is grounded in basic economics: if prices are high, the market signals that more should be produced. Exclusionary zoning in US cities genuinely suppresses construction — single-family-only zoning covers 75% or more of residential land in most major US cities (Manville, Monkkonen & Lens, 2020), making multifamily housing illegal across vast swaths of metropolitan areas. This is a real and well-documented supply constraint with structural roots in exclusionary policy.

Where the mechanism becomes contested is in the transmission from new supply to affordability for low-income households. The standard supply argument relies on filtering theory: new market-rate housing is built for high-income households, who vacate older units; those older units filter down in quality and price over time, eventually becoming affordable to lower-income renters. This is theoretically coherent, and there is evidence that the chain operates over 5–15 years (Mast, 2023; Asquith, Mast & Reed, 2023). But the chain requires time, requires that new construction be genuinely abundant rather than boutique, and breaks down below roughly 50–60% of area median income (AMI) — where the private market has never successfully produced affordable units without subsidy anywhere in the world.

The rent control mechanism claim is similarly partially correct. First-generation hard rent control — price ceilings on all units regardless of tenure — does suppress supply. The literature is clear on this. The claim becomes misleading when extended to all forms of rent stabilization, which are the policies actually in use in most US jurisdictions: inflation-indexed caps exempting new construction, vacancy decontrol provisions, and just-cause eviction rules.

The evidence

The Diamond et al. natural experiment. Diamond, McQuade, and Qian (2019) is the most cited natural experiment in this debate. It studied a 1994 San Francisco ballot initiative that extended rent control to small landlords (buildings with 4 or fewer units built before 1980). Using administrative parcel data, the authors found that rent-controlled tenants were 19% more likely to remain in their apartments — a substantial stabilization benefit. However, landlords responded by converting units to condos, TICs (tenants-in-common), and owner-occupied use, reducing the rental supply of affected buildings by 15% over the following 15 years. The authors estimated this supply reduction increased citywide rents by 7% — a real externality.

This result is routinely cited as proof that rent control harms housing markets. What is less often cited: the same paper found that tenants without rent control were displaced at sharply higher rates, with large effects concentrated on lower-income and minority renters. The welfare calculus is not one-sided. The supply effect is real; so is the displacement harm from removing stabilization. Neither conclusion — “rent control works” nor “rent control fails” — survives the full paper.

Filtering and market-rate production. Mast (2023) used variation in the timing of large apartment building completions to trace vacancy chains through the housing market. He found that a single new market-rate unit creates a chain of approximately 2–3 moves and reaches households with incomes below 120% of AMI within five years. Asquith, Mast, and Reed (2023) found that new apartments built near low-income census tracts reduced rents for nearby existing residents by 4–7%. These results support the supply claim for moderate-income households and nearby renters. They do not show effects reaching households below 50% of AMI, where the supply gap is largest — the National Low Income Housing Coalition estimated a 7.3 million unit shortage of affordable and available units for extremely low-income renters in 2023, a gap the private market has never closed without deep subsidy.

Luxury-only production and income sorting. The supply-only critique also contends that new market-rate production in high-cost cities is effectively luxury-only and concentrates affluent households in central neighborhoods, displacing lower-income residents through amenity upgrading and land value effects. The empirical evidence on displacement from new construction is mixed. Pennington (2021) found that new market-rate construction in San Francisco reduced displacement of nearby low-income residents. Zuk and Chapple (2016) found more complex and neighborhood-specific results. The weight of recent evidence tilts against the strong displacement claim, but the “luxury filtering will reach everyone in time” argument requires a pace of construction — thousands of units annually, sustained — that most US cities have not achieved and that market conditions alone have not produced at sufficient scale.

Inclusionary zoning and the production tradeoff. A genuine tension in supply policy is inclusionary zoning (IZR): requirements that new market-rate buildings include a percentage of affordable units. Developers and supply advocates argue that IZR increases the cost of market-rate production and reduces overall supply (Been, 2010). Inclusionary housing advocates note that without affordability mandates, supply additions serve primarily upper-income households. Both effects appear real; the net welfare effect depends on local market conditions, mandate levels, and whether alternative subsidy mechanisms exist. This is a real policy tradeoff, not a rhetorical one.

International comparators. The supply-only claim derives its strongest international support from Japan. Tokyo’s zoning rules are set at the national level using use-based categories that permit multifamily development across most of the metropolitan area. Tokyo added roughly 2.3 million housing units between 2013 and 2017, compared to roughly 530,000 in all of England over the same period (Hsieh & Moretti, 2019 cite). Real Tokyo housing prices were approximately flat between 1990 and 2020. This is genuine evidence for permissive supply policy.

But the comparative picture also includes counterexamples that complicate the supply-only story. Vienna maintains approximately 60% of its housing stock as public or co-operative social housing (Gemeindebau). Average rents in Gemeindebau are roughly €7/sqm/month versus €17/sqm in the private market. Vienna consistently ranks among the world’s most livable cities and most affordable for its income level. The city achieves this not through market-rate deregulation but through permanent public ownership and cross-subsidy. Singapore has 80% of its resident population in Housing Development Board (HDB) flats — publicly developed, sold to residents at subsidized prices with resale controls. Singapore is a high-income, high-density city where housing unaffordability is contained by public provision. Neither Vienna nor Singapore achieved affordable housing by removing government from the market. Germany operates a large private rental sector with a national rent stabilization law (Mietpreisbremse) that caps rents in tight markets at 10% above local comparative rents. Germany’s rental market functions, new construction occurs, and rents remain more affordable relative to incomes than in comparable US metros — coexisting with regulatory limits on rent increases.

Community land trusts. Community land trusts (CLTs) represent a structural alternative to both supply-only and rent control approaches: land is held in perpetual trust by a community organization, separating land value from housing value and maintaining affordability across ownership transfers. Burlington, Vermont, has operated the Champlain Housing Trust since 1984; resale prices on CLT homes have increased at roughly one-third the rate of market homes over the same period. CLTs are not scalable by themselves, but they demonstrate that alternatives to both markets and state provision exist and function.

Who benefits

The supply-only framing, when deployed to oppose inclusionary zoning, affordable set-asides, tenant protections, and public housing investment, benefits primarily large market-rate developers (NVR Inc., Lennar, D.R. Horton, and similar publicly traded homebuilders) who capture higher per-unit returns on market-rate construction than on subsidized affordable production, and who lobby against inclusionary requirements through industry associations including the National Association of Home Builders (NAHB). Existing large landowners benefit from deregulation that increases allowable development without affordable mandates, since upzoning raises land values.

The supply argument also receives funding and intellectual support from libertarian policy organizations including the Cato Institute and Reason Foundation, whose opposition to rent stabilization and inclusionary zoning aligns with broader anti-regulatory positions rather than a demonstrated commitment to affordable housing production specifically. This does not make the supply argument wrong, but the motivated nature of some of its institutional backing warrants attention when evaluating selective citation of evidence.

Tenants — including the 44 million US renter households, 22.4 million of whom are cost-burdened — benefit from supply expansion to the extent that the filtering chain reaches them. They are harmed by the supply-only framing when it is used to eliminate the tenant protections and affordability mandates that provide near-term relief while long-run supply effects accumulate.

The counter

The supply case deserves a serious steelman. The undersupply of housing in high-demand US metros is not a libertarian talking point — it is documented in peer-reviewed research, reflected in decades of price appreciation, and confirmed by the international Tokyo comparison. The legitimate supply critique is aimed at specific forms of government intervention: single-family-only exclusionary zoning, minimum parking requirements, maximum height limits, setback requirements, and design review processes that add years and cost to approvals. These are not protections for low-income residents — they are protections for existing affluent homeowners who benefit from supply restriction and asset appreciation. The progressive case for supply-side reform is real and has been made by housing economists across the political spectrum (e.g., Edward Glaeser, Alain Bertaud, Jenny Schuetz).

The rent control critique is also partially correct. Hard rent ceilings on all units, regardless of tenure or construction date, do suppress supply over time. The evidence is not in serious dispute on this narrow point. The policy debate is about whether better-designed stabilization — new construction exemptions, vacancy decontrol, moderate inflation caps — avoids these effects while providing meaningful tenant stability. The Diamond et al. (2019) evidence applies to a specific San Francisco ordinance from 1994; its generalizability to modern rent stabilization laws is contested.

The strongest version of the supply argument is not “build anything anywhere” but rather: “the US suppresses market-rate supply far below what would be produced without exclusionary regulation, and that suppression inflicts the greatest cost on the households least able to afford it, because supply restriction keeps prices high across the entire price distribution.” This claim is well-supported. The contested part is whether supply alone — absent public subsidy, tenant protections, and affordability mandates — can close the gap for the bottom quintile of the income distribution. The international evidence suggests it cannot.

References

Asquith, B. J., Mast, E., & Reed, D. (2023). Local effects of large new apartment buildings in low-income areas. Review of Economics and Statistics, 105(2), 359–375. https://doi.org/10.1162/rest_a_01055

Bertaud, A. (2018). Order without design: How markets shape cities. MIT Press.

Diamond, R., McQuade, T., & Qian, F. (2019). The effects of rent control expansion on tenants, landlords, and inequality: Evidence from San Francisco. American Economic Review, 109(9), 3365–3394. https://doi.org/10.1257/aer.20181289

Glaeser, E. L., & Gyourko, J. (2018). The economic implications of housing supply. Journal of Economic Perspectives, 32(1), 3–30. https://doi.org/10.1257/jep.32.1.3

Hsieh, C.-T., & Moretti, E. (2019). Housing constraints and spatial misallocation. American Economic Journal: Macroeconomics, 11(2), 1–39. https://doi.org/10.1257/mac.20170388

Manville, M., Monkkonen, P., & Lens, M. (2020). It’s a zoning problem: The deep roots of housing shortage. Journal of the American Planning Association, 86(1), 49–59. https://doi.org/10.1080/01944363.2019.1688535

Mast, E. (2023). JUE Insight: The effect of new market-rate housing construction on the low-income housing market. Journal of Urban Economics, 133, 103383. https://doi.org/10.1016/j.jue.2021.103383

National Low Income Housing Coalition. (2023). The gap: A shortage of affordable homes. https://nlihc.org/gap

Pennington, K. (2021). Does building new housing cause displacement? The supply and demand effects of construction in San Francisco [Working paper]. https://economics.mit.edu/sites/default/files/inline-files/Pennington_JMP.pdf

Schuetz, J. (2022). Fixer-upper: How to repair America’s broken housing systems. Brookings Institution Press.