Homeowners along much of University Avenue in St. Paul will be able to build small living spaces, often called mother-in-law apartments or granny flats, on their properties.

The St. Paul City Council voted Wednesday to join other cities around the metro that allow the accessory dwelling units. City leaders are aiming to increase density along University Avenue, where the Green Line light rail runs. They also hope the new housing units, which can be attached to a home or detached and built in the yard, will provide affordable housing, more income for property owners and convenient homes for aging residents looking to downsize.

Some residents of St. Anthony Park opposed the units and argued they would change the character of single-family home neighborhoods and reduce available on-street parking.

City leaders did not change the ordinance in response to those concerns.

However, they did make one amendment to the regulations. Initially, the units would be allowed on properties within a half-mile of University Avenue between Emerald Street, on the Minneapolis border, to Marion Street, near the Capitol. But the eastern boundary was moved to Lexington Parkway.

The city previously allowed accessory dwellings only above detached garages in certain areas.

Minneapolis changed its regulations for mother-in-law units in 2014 and allowed the units to be built citywide.

St. Paul council members said Wednesday that they will monitor construction of the housing units along University Avenue before determining whether to allow them in other neighborhoods.