Iowa Legalizes Accessory Dwelling Units

A new law will allow property owners to build ADUs on single-family lots starting on July 1.

1 minute read

May 30, 2025, 6:00 AM PDT

By Diana Ionescu @aworkoffiction


Des Moines, Iowa skyline viewed from a plaza with two flags on either side at dusk.

pabrady63 / Adobe Stock

A new Iowa state law will require cities and counties to allow accessory dwelling units (ADUs) on single-family lots starting on July 1, reports Ryan Kushner in Smart Cities Dive.

“The ordinance, which goes into effect July 1, requires that counties allow a minimum of one unit per lot that’s up to 1,000 square feet or 50% of the size of the single-family home on the property, whichever is larger.”

Kushner notes that the effectiveness of ADUs at easing the housing crisis is as yet unclear. In California, San Jose became the first city to legalize the sale of ADUs as condos last August.

Thursday, May 29, 2025 in Smart Cities Dive

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