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

Montreal Mall to Become 6,000 Housing Units
Place Versailles will be transformed into a mixed-use complex over the next 25 years.

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

DARTSpace Platform Streamlines Dallas TOD Application Process
The Dallas transit agency hopes a shorter permitting timeline will boost transit-oriented development around rail stations.

Without International Immigrants, the Rural US Population Would Be Falling 58%
Census data shows that population growth in rural areas is due in large part to international migrants.

Dead End: Nine Highways Ready for Retirement
The Freeways Without Futures report describes the nation’s most promising highway removal proposals.

Congressman Proposes Bill to Rename DC Metro “Trump Train”
The Make Autorail Great Again Act would withhold federal funding to the system until the Washington Metropolitan Area Transit Authority (WMATA), rebrands as the Washington Metropolitan Authority for Greater Access (WMAGA).
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