Zoning, Inclusionary Policies, and the Path to Scalable Housing Solutions

Housing affordability and homelessness are solvable problems — but only if policymakers pair proven homelessness interventions with supply-side reforms that actually allow more homes to be built. Below I summarize what’s working now, the evidence behind it, and concrete policy actions cities and states can take to translate promise into results.

## The problem, in one snapshot
On a single night, roughly 580,000 people in the United States were experiencing homelessness (HUD Point-in-Time/Homelessness Assessment data). At the same time, the demand for affordable rental housing far outstrips supply: the federal Housing Choice Voucher program serves about 2.2 million households, but vouchers can’t help people if there isn’t affordable housing to use (HUD). These twin facts make clear why we need both effective homelessness programs and deliberate housing production strategies.

Sources: HUD Annual Homeless Assessment / PIT data; HUD Housing Choice Voucher fact sheets (HUD).

## Why zoning and land-use rules matter
Local zoning — especially large swaths designated for single-family homes, high parking minimums, and low-density rules — restricts where and what kind of housing can be built. That constraint drives up prices, restricts supply, and limits the ability of voucher holders and other low-income households to access housing.

Research from the Urban Institute and others finds that removing outright bans on missing-middle housing (duplexes, triplexes, fourplexes), allowing accessory dwelling units (ADUs), and upzoning around transit and job centers can meaningfully increase the pipeline of housing and expand access in high-opportunity neighborhoods (Urban Institute).

Key takeaway: Zoning is not a technicality — it is a principal lever for changing how many homes get produced and where.

## What is working now: reforms that expand supply and affordability

1) Upzoning and allowing “missing middle” housing
– Example reforms: Minneapolis’ 2018 removal of single-family-only zoning, Oregon’s HB 2001 (2019) allowing duplexes/triplexes and other low-density multifamily in many neighborhoods, and local ordinances that allow duplexes or small multiplexes by-right.
– Evidence: Cities that loosened restrictive zoning show higher housing production in rezoned areas and greater opportunities for mixed-income development over time (Urban Institute). Upzoning is not an overnight fix, but it unlocks sites and lowers regulatory barriers that have long prevented developers from building more attainable homes.

2) Legalizing and promoting ADUs
– ADUs (basement apartments, backyard cottages, in-law units) are a low-impact way to add rental units across existing neighborhoods. Where cities simplified permitting, waived impact fees, and offered technical assistance, ADU production rose substantially.
– Why it works: ADUs reutilize existing lots and infrastructure, are relatively low-cost to build, and can quickly add housing for seniors, workers, and small households.

3) Targeted inclusionary zoning (IZ) — when paired with subsidies and design
– IZ requires or incentivizes affordable units in new developments. Mandatory IZ programs produce more units than voluntary ones, but IZ’s scale is limited if used alone.
– Best practice from program evaluations: pair IZ with fee waivers, density bonuses, or direct subsidies to make projects financially viable; calibrate affordability levels to local needs; and use public land or land trusts to scale permanently affordable housing (Urban Institute).

4) Remove counterproductive requirements (parking minimums, excessive lot sizes)
– Parking minimums inflate construction costs and reduce yield on urban sites. Removing them and letting market-driven parking decisions prevail can reduce per-unit costs and encourage denser development near transit.

Sources: Urban Institute analyses on zoning and housing; HUD guidance on compact development and affordable housing programs.

## What’s working on the homelessness side — and why pairing matters
– Housing First and Permanent Supportive Housing (PSH): Strong evidence shows Housing First — rapid access to permanent housing combined with wraparound supports — reduces returns to homelessness and improves health and housing stability (National Alliance to End Homelessness). PSH is particularly effective for people experiencing chronic homelessness and those with complex needs.
– Rapid Re-Housing (RRH): Short-term subsidies and services have high exits to stable housing among families, making RRH cost-effective for many households.
– But limitation: these programs require housing to lease. Vouchers and subsidies work much better when there is enough rental supply — hence the necessity of simultaneous zoning and supply reforms.

Source: National Alliance to End Homelessness (NAEH) resources on Housing First and program effectiveness.

## Two brief case studies that show results
– Oregon (HB 2001): The statewide move to allow duplexes/triplexes and similar small-scale multifamily in residential zones opened legal pathways for new homes in previously single-family-only areas, creating opportunities for lower-cost housing production near transit and services (Urban Institute coverage of state-level reforms).
– Local IZ + subsidies: Jurisdictions that pair inclusionary requirements with local subsidies, fee reductions, or publicly owned land (e.g., some long-running programs in Montgomery County, MD and cities with Mandatory IZ overlays) produce more deeply affordable homes than IZ alone.

## Actionable policy checklist — what cities and states can do now
– Allow more housing types by-right: legalize duplexes, triplexes, four-plexes, and ADUs in single-family zones.
– Upzone near transit and employment centers to increase capacity where demand is highest.
– Remove or reform costly rules: eliminate minimum parking, reduce minimum lot sizes, streamline permitting and approval timelines.
– Design inclusionary zoning to be realistic: pair mandatory IZ with density bonuses, fee waivers, or direct subsidies; target IZ to produce units affordable to very low- and extremely low-income households, not just middle-income bands.
– Couple vouchers with supply policies: expand Housing Choice Vouchers and ensure landlords in newly upzoned areas participate by offering incentives and streamlining inspections.
– Invest in land strategies: use land banks, public land releases, and community land trusts to build permanently affordable housing.
– Fund supportive services: expand Permanent Supportive Housing and Rapid Re-Housing to get people housed quickly and keep them housed.

## Final note — evidence, political strategy, and hope
No single policy ends homelessness or cures housing unaffordability. But the evidence is clear: homelessness programs like Housing First work when housing exists to receive people; zoning reforms and inclusionary policies work when designed with finance and scale in mind. Cities and states that couple rightsizing of zoning with targeted affordability tools and homelessness interventions are the places most likely to make measurable progress.

Policymakers can choose practical, evidence-based wins now: legalize gentle density, streamline approvals, pair inclusionary rules with subsidies, and invest in proven homelessness programs. Those steps — grounded in Urban Institute analysis, HUD data, and the evidence collected and promoted by the National Alliance to End Homelessness — can move communities from crisis response to long-term, equitable housing stability.

For further reading
– Urban Institute — research on zoning, housing supply, and reform opportunities (urban.org)
– HUD — annual homelessness assessment reports and Housing Choice Voucher program information (hud.gov)
– National Alliance to End Homelessness — evidence on Housing First, RRH, and PSH (endhomelessness.org)

Actionable takeaway: Start local. Pass one by-right reform (e.g., duplexes or ADUs), remove parking minimums, and pair a small inclusionary requirement with a density bonus — done together, these three moves expand supply, protect affordability, and increase the ability of homelessness programs to succeed.