LOS ANGELES -- When Charles Durrett and Kathryn McCamant got married and began thinking about starting a family in the early 1980s, they were living in a small San Francisco apartment, both working full time as architects. "Our extended family is scattered all over the country," Durrett said. "We both worked late almost every day. Just to get together with friends took about two weeks of planning. Basically, we saw having a baby in a San Francisco apartment as an isolating affair." Discussing their apprehension with friends, they found similar concerns. Everybody seemed to be living in places that didn't meet their needs. Young couples were spending all their spare time shuttling children to and from day-care centers. Widowed mothers were living alone in the sprawling six-bedroom homes where they had raised their families. Single career people were going broke making mortgage payments, or sharing a house with other singles and arguing about who left the dirty dishes in the kitchen. "We were all 'mis-housed,' " Durrett said. "We've been dealing, at least in the media, with the ill-housed and the homeless. Being mis-housed is not in the serious category with those problems, but it's a problem nevertheless." Now, Durrett and McCamant are certain they have found a solution -- a concept they call "cohousing," which was introduced about 20 years ago in Scandinavia but is virtually unheard of in the United States. Cohousing is "custom-built neighborhoods," planned from beginning to end not by professional developers, but by the people who will live in them. The concept is becoming increasingly popular in northern Europe, where the number has quadrupled in the last five years. They vary in detail and design but essentially provide a mix of privacy and community, combining individual houses with facilities for shared meals, child care and other support systems for a household in which both parents work. At Trudeslund, north of Copenhagen, for example, 33 families live in houses clustered along two streets and a wooded area makes a natural playground for the community's 50 children. The adults, mostly professionals, range in age from 28 to 67. There are four households with no children, nine one-parent households and several singles. A large common house includes a dining hall where most residents eat three or four times a week. Meals are planned and prepared by the adults on a rotating basis, which means each resident cooks one day a month. A cooperative store, laundry facilities, photography darkroom and television room also are located in the common house. Durrett and McCamant, who became interested in cohousing as architecture students in Copenhagen, made Trudeslund their home base when they returned for more study of the concept. After 18 months of travel and research, during which they visited 46 cohousing communities and lived in 15 of them for varying periods of time, they came back to the United States cohousing converts. Their book on the subject -- "Cohousing: A Contemporary Approach to Housing Ourselves" -- has just been published by Habitat Press in Berkeley, Calif., and they spend their free time meeting with fledgling U.S. groups that might be interested in forming their own neighborhoods. Durrett designs day care for the city of San Francisco and McCamant works full time for an architectural firm. "We have a commitment to cohousing mostly based on wanting to live there ourselves {they currently share a six-bedroom Victorian house in Berkeley with another couple}, but also wanting to open it up to other people who we know are unhappy with their situation," Durrett said. "We coined the word 'cohousing,' " McCamant said. "The Danes call it bofoellesskaber, which means 'living communities.' There was this enormous quantity of experience there, which is why we wrote our book -- to put it into useful form." That 200-page reference work not only describes life in eight cohousing communities -- with photographs of pastel row houses lining streets, and houses with solar panels clustered around village greens -- it offers case studies of the development process and essays on such psychological aspects of community living as body language and candid communication. Of course, not everyone embraces the cohousing concept. "The biggest consideration {in American home-buying} continues to be cost: How much down and how much a month," said Dale Stuard of El Toro, former president of the National Association of Home Builders. "I don't think people want a lot of change in housing design. I don't see any revolution coming." Home builders say they keep churning out the same basic house (with ongoing modifications such as larger bedroom suites, more bathrooms, kitchens with microwaves, whirlpools, skylights, round windows, component parts and computerized systems) for a solid reason: This is what middle-class consumers want. Other experts, such as Karen Frank, a specialist in environmental psychology who teaches in the School of Architecture at the New Jersey Institute of Technology, suggest that the American public hasn't been given much choice. "You can't want what you have never seen," she said. Although cohousing developments vary in size (as small as six families and as large as 80 families), location (from inner cities to farm lands), type of ownership, design and priorities, four characteristics are common to all. Durrett outlined the characteristics: Participatory process: Residents are involved from the outset in the planning and design process for the housing development, and are responsible as a group for all final decisions. Intentional neighborhood design, usually with cars relegated to the periphery of the site. "You can't Genie open your garage door and walk into the house, in total isolation." Extensive common facilities. "This is what makes cohousing particularly special. Common dinners have proved overwhelmingly successful, with more than half the residents participating on any given evening." Cohousing also can include a large functional workshop, common laundry and teen-age room. Complete resident management without the intercession of a professional manager. "That sounds burdensome, but they have learned to make a three-hour agenda an hour and a half." Cohousing, they emphasize, also is a lot of work: A new community does not spring into being effortlessly. The start-to-finish time line can take as much as five years, and along the way, participants drop out, others are added and everybody learns a lot about working cooperation. Trudeslund, for example, was launched in 1978, and construction was completed after 2 1/2 years of "hectic and frustrating" meetings by a flood of work groups wrestling with the new challenge of participatory democracy. Upon completion, the price of a house (privately owned) and a share of the common facilities ranged from about $91,400 to $117,700, figures comparable to single-family residences in the area. Durrett and McCamant acknowledge that cohousing is not for everybody. One Danish expert interviewed in their book estimates that "for every 10 families who want to live in cohousing, there is only one that is prepared to take on the burden of the planning period, and for every 10 of those, there are only a few who can take the initiative." Still, they are finding that the response of U.S. audiences echoes the mood they recognized in Denmark. It is a mood reflected in responses to a questionnaire they give people interested in cohousing. "Although there are practical aspects to cohousing, such as saving time and saving money, those are not the things they check first," McCamant said. "They say the same things the Danes say. They want to live in a place with a strong sense of community, a place where you know your neighbors."