Proposed changes that would make it easier for Montgomery County homeowners to build small apartments onto their homes have many residents concerned about unwanted changes coming to their neighborhoods.

Nicknamed “mother-in-law” apartments, accessory apartments are permitted only when homeowners in certain residential zones get permits from the county. Because the special exception process can be costly and time-consuming, the county gets few applications, almost all of which are approved, according to a Montgomery County Planning Department document. The county approves an average of 10 accessory apartments each year.