Duplexes

People in orange safety vests sweeping and cleaning debris in Eaton Fire burn area in Malibu.

Malibu and Pasadena residents will be able to build up to 4 units on fire-damaged properties

The two cities settled a lawsuit brought by a YIMBY group that challenged their ban on multifamily housing in fire-impacted areas.

August 3, 2026 - CALmatters

Grey two-story older home divided into two units inLos Angeles, California with modern apartment building visible in the background.

Study: Legalizing single-family home conversions could nearly double LA's new housing

Research shows that making it easier to turn single-family homes into multiple units could unlock tens of thousands of new units per year.

June 25, 2026 - CALmatters

Houses in Salt Lake City, Utah at dusk.

Salt Lake City Could Allow Backyard Homes on up to 3/4 of Residential Lots

A proposed zoning change would expand the residential areas where accessory units can be built.

March 1, 2026 - Salt Lake Tribune

Aerial view of coastal homes in Pacific Palisades, Los Angeles.

California Group Threatens to Sue Governor Over Post-fire Duplex Ban

A July executive order prohibits property owners from building multiple units in areas affected by the January Los Angeles wildfires.

December 10, 2025 - Politico

Green traditional duplex with red doors.

Harvard Report Cites Zoning, Construction Costs as Obstacles to New Housing

Zoning restrictions and onerous building codes make mid-sized multifamily housing prohibitively expensive or illegal to build.

September 24, 2025 - Smart Cities Dive

Heavy smoke from Palisades Fire burning in hillsides with homes with downtown Los Angeles visible in background.

Palisades Homeowners Barred From Rebuilding With Duplexes

The California governor and L.A. mayor issued identical executive orders banning multi-family development in areas destroyed by the Palisades Fire.

August 6, 2025 - Reason

Homes destroyed by Palisades Fire in Los Angeles, California.

What Housing Crisis?

Los Angeles Mayor Karen Bass issued an executive order that prohibits the construction of duplexes, triplexes or fourplexes from replacing single-family-homes destroyed by the recent wildfires in Pacific Palisades, i.e., the suspension of SB 9.

August 4, 2025 - LAist

Colorful bright blue small houses with decorative cacti in courtyard in San Diego, California.

Opinion: How to Rebuild the ‘Starter Home’ Market

Large minimum lot sizes and restrictions on multi-unit housing put an artificial floor under home costs. Is it time to eliminate them?

June 24, 2025 - Greater Greater Washington

Google Street view screen shot of modern duplex built between two historic homes in Cliffside Park, New Jersey.

New Jersey Duplexes Elicit Mixed Reactions

Modern, two-unit residences are proliferating in northern New Jersey communities, signaling for some a boon to the housing supply and to others a loss of historic architecture.

June 8, 2025 - Gothamist

View of downtown Dallas, Texas skyline with skyscrapers against twilight sky.

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.

May 15, 2025 - Strong Towns

Row of two-story homes in Boulder, Colorado.

Proposed Boulder Ballot Measures Call for Impact Fees, Affordable Duplexes

Boulder residents are working to put two housing-related proposals on the November ballot.

May 6, 2025 - Boulder Reporting Lab

Two pastel green/blue front doors on duplex with decorative wreaths.

How Single-Family Conversions Benefit Both Homeowners and Cities

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

March 4, 2025 - Strong Towns

View of Missoula, Montana on a sunny day.

Montana Supreme Court Upholds Zoning Reform Bills

The decision invalidates a preliminary injunction that blocked two key housing bills.

September 8, 2024 - Daily Montanan

Maricopa County, Arizona

Arizona Legalizes ADUs and Higher Downtown Density Statewide

Two new laws require cities to permit ‘missing middle housing’ near city centers and ADUs on all single-family lots.

May 28, 2024 - The Real Deal

Aerial view of Anchorage, Alaska downtown with mountains in background at golden hour.

Anchorage Leaders Debate Zoning Reform Plan

Last year, the city produced the fewest new housing units in a decade.

March 28, 2024 - Anchorage Daily News

Nebraska capitol building against a blue sky

Nebraska Considers State Zoning to Increase Housing Density

The bills would require cities to adopt zoning regulations to allow duplexes and ADUs.

February 1, 2024 - Unicameral Update

Aerial view of Whitefish, Montana with fall colors and mountains in background.

Montana Judge Blocks Zoning Reforms

The decision reverses new laws once dubbed the ‘Montana Miracle.’

January 3, 2024 - Reason

Three two-story houses on residential street in Detroit, Michigan. Center house appears abandoned.

Detroit Launches Duplex Repair Program

The grants will help landlords repair aging multifamily affordable housing.

November 3, 2023 - City of Detroit

St. Paul skyline as seen from across river

St. Paul Approves Zoning Reforms

The zoning updates will permit multi-unit housing and promote transit-oriented development to boost the city’s housing supply.

October 20, 2023 - Pioneer Press

A map of zoning codes in the Michigan city of Traverse City.

ADUs, Minimum Lot Sizes, and Quadplexes Under Discussion in Traverse City

Zoning changes for everything from housing density to minimum lot sizes are under consideration for a city on the shores of Lake Michigan.

August 29, 2023 - The Ticker

FREE Course: Walkable City 1: Why Walkability?

After describing his path towards focusing on walkability as the essence of good planning, Jeff Speck marches through his five principal reasons for making more walkable places.

Reinventing Malls: Planning Alchemy—Turning Gray Fields Into Gold

The course focuses on the opportunities and imperatives that shape reinvention of mall sites.

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