Converting single-family homes to triplexes can ease the housing crisis and offer affordable, flexible options for more households. Why is it largely illegal?

A “Multigenerational Roommate House” outside of Dallas offers a model for affordable multifamily housing — if only it’s made legal in more places.
The home’s owner, Monte Anderson, “applied some savvy interpretation of local zoning rules to transform it into a legal, owner-occupied, multiunit home for five single adults ranging in age from almost twenty to over 70.” The units have separate entrances, bathrooms, and kitchenettes (full kitchens would trigger a zoning violation).
This style of housing is illegal under most U.S. zoning codes, explains Lauren Ronnander in an article for Strong Towns. But advocates for reform argue that allowing single-family conversions to duplexes or triplexes “can give residents the flexibility to live where they want at a price they can afford.”
According to Ronnander, allowing duplex conversions can also raise property values and, in turn, local tax revenue, benefiting cities. “In cities that make this type of housing legal by right, thousands of stagnant properties can be improved, raising property values, increasing tax revenue and revitalizing aging neighborhoods.” Legalizing single-family conversions can create more housing choices while avoiding the opposition and infrastructure costs that come with larger multifamily projects.
FULL STORY: This “Multigenerational Roommate House” Shows How To Heal the Housing Market

Planetizen Federal Action Tracker
A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

Walmart Announces Nationwide EV Charging Network
The company plans to install electric car chargers at most of its stores by 2030.

Chicago Approves Green Affordable Housing Plan
The Mayor’s plan calls for creating a nonprofit housing corporation tasked with building affordable housing that meets Green Building standards.

Dallas Code Reform Makes Way for Missing Middle Housing
The Dallas City Council voted to change the city’s building code to allow up to eight residential units in three-story buildings.

Mahjong Game Highlights Displacement of Seniors in NYC’s Chinatown
‘Aging Out of Place’ explores the mechanisms that displace vulnerable seniors, and how the community can help preserve key resources and institutions.

Poland Building £25B Transit Hub
The mega project will include an airport and links to high-speed rail lines.
Urban Design for Planners 1: Software Tools
This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.
Planning for Universal Design
Learn the tools for implementing Universal Design in planning regulations.
City of Moorpark
City of Tustin
City of Camden Redevelopment Agency
City of Astoria
Transportation Research & Education Center (TREC) at Portland State University
Regional Transportation Commission of Southern Nevada
Toledo-Lucas County Plan Commissions