Multigenerational living is bringing families in Atlanta’s intown communities and suburbs closer together, especially as parents move in with their adult children.

Sometimes the decision is focused on finances, reducing the number of mortgages and sharing the cost of living in a home. Other times, grandparents are taking care of grandchildren, or adult children are caring for aging parents.

Area builders are adapting and updating homes to add space, privacy and aging-in-place features. Anthony F. Pourhassan, owner of Highlight Homes, said he's been asked numerous times in the past few years to design and build additions to accommodate parents.

Interior designer Randi Destefano has been asked to look at potential properties with clients.

“They’ll call me in to view a house with them and their real estate agent, just to see how much work might need to be done to make that house livable and to maybe get two masters,” said Destefano. “Sometimes it means they don’t get that house because it’s going to be cost prohibitive.”

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Here are a few of the options, when baby boomers or elderly parents move in with their kids.

Transforming the guest house

A guest house, carriage house or pool house can take on a new role. Dave Radlmann, owner of Heirloom Design Build, has built homes in Inman Park with carriage houses up to 700 square feet.

“On all the houses, we’re definitely thinking about accommodations for people’s in-laws or parents,” Radlmann said. “If the lot can accommodate it, we already try to get a carriage house with living quarters in it. This will help create a little more separation between both families.”

The floor plans separate the bedroom from the living/dining area and kitchen, or it can be open to the living area, with a partial wall or no wall. But he said some people are concerned that a separate space will be an eyesore.

“They can fit very well in the landscape and actually be quite an accent for your yard,” he said.

Some options include prefabricated units, which some call "granny pods." Virginia-based MedCare Systems' senior living cottages are designed for aging or disabled individuals. The MEDCottage, averaging 300 square feet, has a bedroom, bathroom and kitchenette. Extra features include special flooring that prevents falls, and cameras and remote monitoring systems that alert someone of a medical problem.

MEDCottages cost up to $85,000, and units can run up to 700 square feet, said Chris M. Cummins, executive vice president for MedCare Systems.

For these and other structures, homeowners need to check with your county, city and neighborhood to make sure they are allowed on your property, Destefano said.

“You, the new caregiver, can rest easily knowing you are going to step out the door and know your mom is OK,” said Margaret Barnett, an interior designer and owner of Barnett+Co.

Expanding the home

Some families desire to expand the size of the home, adding a second master bedroom or other spaces. The national average cost for a midrange master suite addition is $106,196, according to Remodeling magazine’s 2011-2012 Remodeling Cost vs. Value Report. The report also showed that a master suite addition could recoup about 60 percent of the cost.

"I have had people add a master suite and then turn over the original master suite to that aging parent," said Mark Buelow of Distinctive Remodeling Solutions, based in Roswell. "You're truly creating value because you're adding a bedroom with a bath."

In 2012, a two-story addition cost an average of $165,796 nationally, according to the Remodeling magazine report, with the possibility to recoup 62 percent of the costs.

John Beach, a partner in Atlanta-based Paces Construction Co. and a certified aging in place specialist, expanded a Brookwood Hills home built in the 1920s for his clients, who are in their 80s.

The project required tearing off a previous addition on stilts and then building an addition with a suite on the ground floor for their daughter, a nurse, and space for the parents above (an elevator provides access to those floors and a third story with room for the grandkids and storage). In the parents’ bathroom, he built a higher toilet, curbless shower with bench, and a long-reach hand spray and handrail.

The National Association of Home Builders says “shadow units,” which are built alongside the home or separate units that access the main floor, are a trend in multigenerational living.

A Connecticut-based company has introduced its modular home additions, called PALS (short for Practical Assisted Living Structures). The one- and two-bedroom pods are handicap accessible and can be attached to the home, connected to rooms on the first floor. The structures, about 14 by 24 feet, also can be placed on the property on a temporary basis. A front door provides a separate entrance, for privacy and independence.

The structures can be placed on Georgia properties, although homeowners need to see if a variance is required, depending on their community, said Alison Rhodes, president and CEO of PALS Built.

Building out the basement

When Edith Wichser’s father-in-law, Bill, moved in into her Roswell home, the obvious choice was to finish their basement. Working with Buelow, of Distinctive Remodeling Solutions, Edith Wichser and her husband, Karl, outfitted the basement with a bedroom, bathroom, living area, office and kitchen as well as aging features for Bill, now 97.

The national average cost for a basement remodel is $63,378, according to Remodeling magazine’s 2011-2012 Remodeling Cost vs. Value Report.

The entrance to his bedroom has 3-foot-wide doorways, large enough for a hospital bed to be rolled out or in from the terrace. In the kitchen, an area was recessed underneath the sink, in case a wheelchair was needed. The bathroom has a curbless shower with a built-in bench, grab bars and slip-resistant tile.

The basement also has a recreational area for their 12-year-old son.

Wichser said her father-in-law often would come out and interact with the boy, talking sports or asking about video games.