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.

The proposed change would make it easier for residents to apply for licenses to add the apartments by allowing homeowners in some residential areas to add them without getting a special exception.

"A lot of what we're proposing is to allow flexibility for families," said Valerie Berton, spokeswoman for the Planning Department. For example, the apartments are useful for families who want to take care of an aging parent or who have children in their 20s who can't afford their own places, she said.

The apartments will increase the availability of affordable housing in the county without increasing sprawl, and they will give homeowners an added source of income, Planning Department Zoning Coordinator Greg Russ said in a presentation.

But many Montgomery County residents are concerned that the regulations will hurt their quiet, single-family neighborhoods.

Increased neighborhood density could create problems for areas where schools are already crowded -- like the Bethesda-Chevy Chase area -- as well as raise public safety concerns, said Naomi Spinrad, vice president of development of the Chevy Chase West Neighborhood Association.

For Bethesda resident Jennifer Lavorel, more apartments means a harder time finding parking near her home. The apartments will increase the density in her neighborhood, she said. Though she is supposed to have dedicated parking, there is no enforcement to prevent someone from parking in her spot.

"The question now is whether [the Department of Housing and Community Affairs has] adequate resources to do the enforcement they need to do now," Spinrad said.

Agency representatives could not be reached for comment.

"My husband and I worked hard to buy this house. We specifically bought it in this community because it's single-family," said Susan Stevens of North Potomac. "They're just going to let it turn into boarding houses. They're even OK if someone puts a shed in their yard and rents it out."

Stevens said she suspects several houses in her neighborhood already have unlicensed accessory apartments that go unchecked by the county. "It's usually the worst-looking house on [each] street."