Citing Lack of ADU Development, Ann Arbor to Refine its ADU Ordinance

After legalizing accessory dwelling units in 2016, the city of Ann Arbor hasn't added many accessory dwelling units. Some regulations designed to limit the number of ADUs developed have made the building type impossibly cost prohibitive.

1 minute read

November 13, 2018, 7:00 AM PST

By James Brasuell @CasualBrasuell


Residential Development

Rungtiwa P / Shutterstock

"[The] Ann Arbor city council is considering ways to make it easier for homeowners to create accessory dwelling units on their property," reports Lauren Slagter.

After achieving very little development of accessory dwelling units (ADUs) since approving an ordinance to allow the construction and rental of accessory dwelling units in 2016, the Ann Arbor City Council is ready to retool the ordinance to encourage more development.

"The ordinance included restrictions intended to prevent the proliferation of ADUs across the city, and now city council thinks the restrictions may have worked too well," according to Slagter.

Most of the lack of ADU development in the city is credited to the high cost of building the units. According to Slagter, the city already dropped a previous requirement for every detached ADU to have its own water and sewer hookup, separate from the main house. Removing that requirement dropped the price of constructing an ADU by $20,000 to $30,000. Possible refinements of the city's ADU ordinance include removing maximum size regulations; removing minimum lot size requirements; allowing ADUs on lots with single-famly zones, regardless of zoning; and more.

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