# Patch Notes #002: Housing / Homelessness Source Appendix

Version: v0.1 public source appendix
Date: 2026-07-03
Status: Baseline source list, not final evidence review.

## HUD AHAR / PIT Count

Use for official homelessness estimates and categories. Caveat: PIT is a point-in-time estimate and does not capture every form of housing insecurity.

- HUD Exchange AHAR reports: https://www.hudexchange.info/homelessness-assistance/ahar/
- HUD 2024 AHAR Part 1 PDF: https://www.huduser.gov/portal/sites/default/files/pdf/2024-AHAR-Part-1.pdf

## Harvard Joint Center For Housing Studies

Use for national affordability, rent, homeownership, cost burden, and market trend framing.

- State of the Nation's Housing 2025: https://www.jchs.harvard.edu/state-nations-housing-2025
- State of the Nation's Housing 2026 PDF: https://www.jchs.harvard.edu/sites/default/files/reports/files/Harvard_JCHS_The_State_of_the_Nations_Housing_2026_0.pdf

## Freddie Mac Housing Supply

Use for supply-shortage framing. Caveat: shortage estimates are national and must be localized before policy recommendations.

- Housing Supply: Still Undersupplied by Millions of Units: https://www.freddiemac.com/research/insight/housing-supply-still-undersupplied

## National Low Income Housing Coalition

Use for low-income rental affordability and wage/rent gap framing.

- Out of Reach 2025: https://nlihc.org/oor

## Housing First / Permanent Supportive Housing

Use to separate high-need chronic homelessness interventions from general housing affordability policy. Caveat: housing stability, health, criminal justice, cost, and community outcomes should be evaluated separately.

- USICH Housing First resources: https://www.usich.gov/guidance-reports-data/federal-guidance-resources/housing-first
- HUD Exchange, Housing First in Permanent Supportive Housing: https://www.hudexchange.info/resource/3892/housing-first-in-permanent-supportive-housing-brief/

## Eviction Prevention

Use for upstream prevention and tenant-stability questions. Caveat: evidence depends heavily on targeting, legal context, program design, and rental-market conditions.

- Eviction Lab: https://evictionlab.org/
- Urban Institute housing and communities research: https://www.urban.org/research-and-evidence/housing-and-communities

## Zoning, Permitting, And Supply

Use for land-use, permitting, and housing-production constraints. Caveat: national supply claims must be localized; local infrastructure, fiscal incentives, and political constraints matter.

- Brookings housing topic page: https://www.brookings.edu/topics/housing/
- White House statements and releases on housing supply and affordability: https://www.whitehouse.gov/briefing-room/statements-releases/

## Next Source Pass

- Rapid rehousing and shelter outcome comparisons.
- Construction cost and labor/material constraints.
- Local fiscal incentives and municipal finance.
- Supply elasticity and zoning causal estimates.
- Voucher utilization, landlord participation, and administrative failure points.
- Population-specific homelessness evidence: families, youth, veterans, domestic violence survivors, chronically homeless adults, and system exits.