Minneapolis officials are closer to approving a new breed of housing that would allow homeowners to build and rent out a separated residence on their property.

The so-called accessory dwelling units could one day become a new, affordable living option for renters or aging family members in some of the city's many residential neighborhoods. They would simultaneously provide a steady source of income for homeowners struggling to pay for and maintain a larger house.

"I believe it will provide affordability for families, flexibility for shifting demographics in the city of Minneapolis and better land use," said Craig Wilson, a principal at sustainable development firm Sustology, at a city planning commission meeting Monday.

The planning board voted to approve the ordinance change, authored by Council Member Lisa Bender. The measure has already been the subject of five public open houses and now goes to the council's zoning and planning committee.

Accessory dwelling units generally have their own cooking, sleeping and bathroom facilities. The proposed changes would allow a homeowner to renovate an attic, basement or build an addition to become a rental unit. Homeowners could also create the so-called "granny flats" over garages or build stand-alone cottage-like living spaces.

The proposal would require attached structures to match the exterior look of the existing house, and detached ones to be solidly built with durable materials. They would not require an additional parking space.

Planning commission members decided to raise the maximum height to 20 feet, but detached structures cannot exceed the height of the existing house. They also tweaked the maximum floor area for the detached units to add flexibility.

Planning commissioners tried to strike a balance between allowing usable spaces without permitting giant, separate structures on urban lots.

"We're trying to get to a habitable unit, one that will actually get built," said planning commission president Ted Tucker. "But we don't want to dominate neighborhoods with second houses in the back."

The ordinance would also require that one of the two residences be occupied by the owner, making the accessory dwelling units distinct from duplexes scattered around the city.

Many other cities across the country already allow similar units, including Seattle, Portland, Denver and even Bloomington.

Everyone who attended Monday's meeting testified in support of the change. Most of the nearly 200 residents who answered a city survey on the issue were supportive.

"It will provide hundreds if not thousands of units of affordable housing seamlessly integrated into our neighborhoods, into the walkable areas where people are wanting to live," said Max Musicant, who runs a firm that seeks to better utilize public spaces. "And it will also save countless numbers of historic homes by making them economically more viable and preventing teardowns by accommodating changing preferences."

Eric Roper • 612-673-1732

Twitter: @StribRoper