How Cities Can Support ADU Production

Although state-level laws are making it easier for homeowners to build accessory dwelling units, high impact and development fees remain a major barrier for many prospective ADU builders.

1 minute read

November 14, 2024, 8:00 AM PST

By Diana Ionescu @aworkoffiction


Craftsman-style two-story home with detached converted garage apartment accessory dwelling unit.

A detached garage converted to an accessory dwelling unit. | Sightline Institute: Missing Middle Homes Photo Library, CC BY 2.0, via Wikimedia Commons / Wikimedia Commons

While many states are liberalizing regulations related to accessory dwelling units (ADUs) to make ‘granny flats’ easier to build, “local governments remain the key gatekeepers when it comes to ADU liberalization,” writes Mike Koenig in HousingWire.

For Koenig, there’s still work to do to ensure property owners around the country can easily and affordably build backyard cottages or other add-on units on residential lots that can help gently increase density and improve housing affordability.

“As state legislatures continue to press municipalities to ease or remove ADU-related restrictions (13 and counting have done so), utility and other fees—collectively known as impact fees—move toward the center of pro-ADU policy discussions. That’s because impact fees can add up to more than enough to stifle ADU development.” Koenig recommends a few ways cities can ensure their regulations aren’t limiting ADU production, including prorating impact fees and waiving certain development fees.

Koenig points out that the higher density created by ADUs can bring long-term benefits to the community beyond housing affordability, including higher tax revenues. But while costs and other barriers remain high, “States and municipalities have come a long way in smoothing the paths forward for those who hope to add vital infill housing through ADUs.”

Monday, November 11, 2024 in HousingWire

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