Until recently, we had to make do accommodating aging parents or grown children who wanted to live with us.

But economic downturns, the rising cost of housing and elderly care, and the desire to keep the family together under one roof have motivated homebuilders to craft floor plans with dedicated, not makeshift, living quarters to shelter two or more generations.

Instead of converting a spare bedroom or an unused office into a mini home for a family member seeking privacy, or transforming the daylight basement into a self-contained flat, designers have created multigenerational dwellings -- “gen home” for short -- that incorporate a home within a house.

Inside the main house is a “gen suite,” a term first popularized by the Lennar Corp., which introduced its NextGen floor plan in 2011 after the recession and foreclosure crisis, when extended families moved back in together to save on housing costs.

Since then, Lennar’s NextGen homes have been purchased for more than financial benefits or to split childcare and household chores, says Kelcie Kromminga, Lennar’s marketing specialist in the Portland division. Families who have an adult child with special needs or those wanting private space for a hobby or a longterm visitor are interested in the flexible, extra living spaces, too, she says.

Lennar is one of the largest homebuilders in the U.S. with almost 50,000 new homes sold in 2018, according to Builder news. A fraction, about 3 percent, of the company’s 1,700 new homes built in Oregon and Washington state this year will contain a second home, says Kromminga.

Lennar’s NextGen homes fit on a standard-size lot and don’t need a bigger footprint than the company’s one-home floor plans. “The most significant added costs are for the additional appliances and cabinets and private patio,” says Kromminga.

Lennar’s NextGen homes fit on a standard-size lot and don’t make a bigger footprint than the company’s one-home floor plans.

A NextGen home in the new Jennings Lodge Estates community, between Milwaukie and Gladstone, has a two-car garage next to a single-car garage. The well-planned division starts here.

Walk past the front door of Lennar’s Camden model home and to the end of the Craftsman-style covered porch. Round the corner and, on the side of the house, you’ll see another front door that opens to separate living quarters that are more than a bedroom. There’s also a living room, kitchenette, laundry and bathroom. An interior door opens to the wide hallway in the main house.

The 2,507-square-foot, single-level generational house has three more bedrooms and two more bathrooms. Prices start at $579,900. Smaller houses in the new 72-site development are $500,000 and more.

Stone Bridge Homes NW's multigenerational home.

Search the Open Listings real estate database and you’ll find a range of homes for sale with “next gen” accommodations, from a traditional two-story with 3,183 square feet of living space, at 14603 200th Ave. E #74 in Bonney Lake, Washington, for $569,950 to an almost $8-million estate with a 9,000-square-foot French Provincial-style mansion on a half acre at 122 Canyon Creek in Irvine, California, where the main-level, next-gen master suite opens directly to the backyard garden.

The annual NW Natural Street of Dreams home tour, which has been displaying the latest building trends and techniques for 44 years in the Portland area, has showcased a house for two or more generations for the last decade.

One of the new houses in the 2019 tour in Wilsonville this summer was BC Custom Construction’s sweeping, single-story dwelling designed to offer privacy as well as places to gather for a mother and her grown son. There is a master suite on both ends of the 4,072-square-foot residence; a wing for each generation.

Stone Bridge Homes NW's multigenerational home in Happy Valley.

History of generational living

It was not uncommon before World War II for extended families to live together. Adult children stayed at home while going to school, finding a job or saving money to buy a home of their own.

Housing booms and the push to have a place in the suburbs propelled young families to set out on their own. During economic declines, however, families have moved back in with each other.

Kelly Ritz, president of the Home Builders Association of Metropolitan Portland, which organizes the Street of Dreams, likes to talk about the evolution of homes built for multigenerational living.

Ritz, who is also president of Stone Bridge Homes NW, says new houses on a standard 5,000-square-foot lot built 30 years ago typically had a garage in front and a study off the entry.

Stone Bridge Homes NW builds homes has separate living quarters for families that are doubling up.

Over time, the unused study morphed into a guest bedroom conveniently on the main floor. A closet was added. Then the guest bathroom became a full bathroom. “So you could have someone staying with you or living with you, like an elderly parent, who could go directly from the driveway into the house,” she says. “It was accessible.”

The guest suite found permanent occupants due to cultural or financial factors, or the need for a live-in caregiver.

“With housing costs, you may need Mom and Dad to pay half the mortgage, and if both young parents work, grandparents can be there to help with the kids,” Ritz says.

In “multigen” remodeling, attics, garages and basements are remade into sleeping quarters. Prefabricated micro units or secondary homes, also known as accessory dwelling units, are being installed in backyards.

Concepts are being refined, Ritz says. New houses are designed to provide some separation, so people can have privacy and interact when they want to. The challenge is having a common area. “No one wants to feel as if they’re relegated to just their bedroom,” she says.

Unlike accessory dwelling units, Ritz has found that people who buy new houses with second living quarters aren’t looking for a rental opportunity. “Most of the generational homes are purchased by people who have an extended family,” she says.

Right now, generational homes are not in huge demand, but there is a demand, Ritz says. “And we’re happy to provide it. If it’s helping two families pool their resources to have a nice place to live, and it helps family members with health or mobility issues, that’s great.”

Renaissance Homes started designing plans for multigenerational living about three years ago and will continue to work on new plans, says Nancy Haskin, the builder’s director of sales and marketing.

6 Renaissance Homes has multigenerational condos

Renaissance Homes has condos with a separate bedroom, bathroom, kitchenette and closet for a stackable washer and dryer. The lower level space can be entered from the outside or a door from the main house off the garage.

“These alternative spaces can be used for either an in-law or college graduate coming back home,” says Haskin.

In Lake Oswego, Renaissance Homes designed a daylight basement as a family room with a bar area that can be used as a kitchenette. There is also a bedroom and bathroom on the level.

”This can be for a large family or multigenerational family with in-laws," she says. “We also included full en-suite bedrooms on the upper floor.”

Haskin says her company is working on additional home plans that incorporate two master bedrooms on the main level or a smaller master suite on the main level with the primary suite on the second level.

"We believe with the baby-boomer generation retiring, we are going to be able to utilize this type of plan with many families,” she says.

--Janet Eastman | 503-294-4072

jeastman@oregonian.com | @janeteastman

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