On a chilly evening in Minneapolis in 2019, residents gathered in a crowded city council chamber to debate a radical idea: eliminating single-family zoning across the entire city. For over a century, the rule that only one house could sit on a lot had shaped neighborhoods, pushed up prices, and limited who could live where. But that night, the council voted to open the door to duplexes and triplexes on every residential parcel.

The move made national headlines. And it sparked a broader trend—planners and developers across the country began to ask: What if the very codes we’ve lived by are the biggest obstacle to affordable housing?

From Restriction to Opportunity

For decades, zoning has acted like invisible scaffolding, quietly dictating how communities grow. In places like California, 70% of residential land has been reserved exclusively for single-family homes. Meanwhile, demand has surged, populations have grown, and affordability has collapsed.

Developers and planners are now teaming up to flip that script. Instead of treating zoning as an immovable barrier, they’re working together to rewrite the rules—making space for more density, more housing types, and ultimately, more affordability.

Stories of Change

• Portland, Oregon: In 2020, Portland passed its “Residential Infill Project,” allowing up to four homes on most lots. Developers responded quickly, introducing designs for courtyard apartments and compact clusters of homes that blend into existing neighborhoods while dramatically increasing supply.
• California: Statewide reforms have legalized accessory dwelling units (ADUs) and duplexes in once single-family zones. Suddenly, homeowners are partners in the density movement—turning garages, basements, and backyards into new housing that meets community needs.
• Arlington, Virginia: After years of debate, Arlington voted to allow “Missing Middle” housing like townhomes and small multiplexes in single-family areas. The push came from both community advocates and developers who saw an opening to build more inclusive neighborhoods near transit hubs.

Each of these examples tells the same story: zoning reform is no longer a hypothetical—it’s happening in real time, and it’s reshaping the map of American housing.

Developers as Co-Authors

What’s striking about this moment is how real estate developers are stepping into the role of co-authors. Instead of fighting zoning on a project-by-project basis, many are working with planners to rethink the code itself.

For example, some cities are offering density bonuses—the right to build taller or with more units—if developers commit to affordable housing. Others streamline permitting for projects that include a mix of incomes. These shifts give developers predictability while giving communities the housing they desperately need.

As one Portland architect put it, “We’re finally building for people, not just parcels.”

The Road Ahead

Rewriting zoning codes won’t solve the housing crisis overnight. Communities will still wrestle with concerns about parking, traffic, and neighborhood character. But the momentum is undeniable: cities are recognizing that the old rules don’t match today’s challenges.

By embracing density, rewriting zoning, and partnering with developers, communities are laying the groundwork for a more affordable future—one duplex, ADU, or courtyard apartment at a time.