An accessory dwelling unit (ADU) is a smaller home that shares the same residential lot with a larger home. Communities are allowing ADUs as a gentle way of adding new housing options with existing neighborhoods.
Above a detached garage
In the
back yard
You can add an accessory dwelling unit to an existing home in many different ways, making them a uniquely flexible housing option.
The Trust Fund has produced a new fact sheet highlighting the current state of accessory dwelling unit policy in Greater Des Moines.
We joined local non-profit HOME, Inc. to follow their construction of an accessory dwelling unit in the Oak Park neighborhood from start to finish. Each episode features an update from the project site as well as an interview with a local housing expert.
Two Houses, One Home is hosted by Kourtney Kirkpatrick of HOME, Inc.
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ADUs provide a flexible housing option that can evolve with families through all phases of life. Homeowners can rent them for additional income. They could be a place for an adult child to live after college. Or for an aging parent to live independently in retirement-the options go on from there.
Your local government's zoning policy typically determines whether you can build an ADU at your property and what the requirements are for doing so.
While multiple Greater Des Moines communities allow ADUs in some form, their policies can vary widely. It's always best to contact your city's community development or building permitting officials to ask about policies near you.
The communities listed below responded that they allow ADUs in at least some areas.
Below, "by right" approval means a homeowner would predominantly work with city staff for the ADU to be approved. "Conditional" approval means a conditional use permit or similar approval must be issued, which usually involves a vote by a zoning board of adjustment or other local body.
Conditional Des Moines Pleasant Hill Polk County** Polk County in the table refers to unincorporated areas of the County that are not part of any city.
Local policies for ADUs vary widely, but here are some current trends to expect based on our survey:
Always contact your local government's community development or building officials for complete information about local policies.
ADUs can cost between $50,000 and $150,000+ to add to a house, and they may rent at prices that are beyond the reach of people struggling most to afford the place they live. But ADUs do provide a new housing option that matches well with existing neighborhoods where it might otherwise be difficult to build.
Another benefit of ADUs is the land they sit on is already paid for - and they make good use of existing community infrastructure like roads, utilities, parks and more while providing a housing option many neighbors may never even notice.
In 2022, the City of Des Moines dramatically expanded where ADUs are allowed to be constructed, increasing their potential as a housing solution in our community.
Here's where you can learn more about this housing option:
