Co-housing is not a well known term in real estate but it is a growing housing movement. It is also called "intentional communities," but if you were around in the 1960s the word "commune" may pop into mind. Co-housing, however, is a very different concept.

Communes were usually built by residents with unifying interests or concerns. Commune dwellers might all be vegetarians or practicing an alternative religion. Often they were united by economic factors such as farming or arts and crafts. In a commune togetherness could be intense; land and buildings were jointly owned or leased and cooking, childcare, maintenance and other tasks were shared or perhaps mandated would be a better term. Co-housing is more likely to attract very diverse groups of people who want to explore a different form of socializing while maintaining privacy and owning their own property.

The idea of co-housing came out of Denmark in the early 1980s and it continues to be a major force in that country with over 200 active communities. In the United States it is estimated that there are 80 active co-housing communities up and running throughout the country and another 100 in the planning stage.

In its purest form co-housing is built from scratch and designed with the goal of unifying the residents and encouraging social interaction. There are developers who specialize in organizing, marketing, and building intentional communities but most have started with two or three families interested in the lifestyle that locate a site and recruit other members. The participation of as many potential residents as possible in the design process is considered crucial to the success of the project. The Cohousing Association of the United States lists communities in its database that range in size from seven to 67 residences but says that most co-housing has 20 to 40 member families.

Housing can be detached single family units, townhouses, or garden style condominiums. Typically the living units are clustered to allow a lot of green space or built around a common courtyard. Cars and roads are, wherever possible, kept on the outskirts of the development both as a safety issue for children but also to allow both a visual and physical flow among houses. Meandering pathways, playgrounds, and community gardens are frequent amenities. There is almost always a club-house or gathering space with a kitchen and room(s) for meeting, dining, and socializing. Perhaps there is also a workshop or a library for group use. Preparation of and participation in community meals (which tend to be served two or three times a week) and other activities is entirely voluntary.

Legal ownership takes one of three forms. Many developments are owned as single family houses with each resident holding a fee simple deed while the community rooms and possible open land are owned by a homeowners association. Some are held under cooperative ownership but this is a format that banks outside of New York, Washington, D.C., and a few other major cities are not too comfortable financing. The condo model seems to work best from a financing standpoint with land and common areas held under a master deed and the homes owned individually. This is a format that banks are familiar with and one which allows homeowners to buy and sell their properties at will without a vote of the community.

Another model that has emerged is what is referred to as retrofit co-housing. This is an evolutionary model which may take a full generation to reach fruition but starts when one or two families buy into an existing neighborhood, recruit possible participants, and wait for other houses to come on the market either for sale or under long term lease. As more and more houses are acquired by members the neighborhood is adapted to meet the needs of the community; fences are torn down, common areas established, existing streets are "quieted," and eventually a common kitchen/gathering area is built. This has not been a particularly successful model but co-housing experts point to N Street Housing in Davis, California as a good example.

Much attention is now given to elder co-housing. This looks a lot like those independent living projects that companies such as Marriott have been developing for affluent seniors. Usually based on a condominium model (although many are rental communities) these allow older residents (usually defined as 55 years of age or older) to maintain their own apartments but encourage or require that one meal per day be eaten communally.

Elder or senior co-housing is more informal and flexible. First, the development is designed with the goal that residents will be able to "age in place" with accessibility and security the primary concerns. Some interesting concepts have emerged. One is studio apartments within individual units so residents can have live in aides and perhaps share those aides with neighbors to lower costs and prolong non-institutional living

On the outer edges of co-housing is yet another model, eco-housing. These developments are usually structured legally and socially along co-housing lines but with a greater emphasis on sustainable and green living. Features of such developments may include community organic gardens, composting toilets or watershed sensitive waste treatment plants. These are worthy of further examination as we continue to look at green building and living.

What is it like to live in a co-housing development? There is certainly a strong element of self-selection that goes into the composition of these communities so anyone who opts in is somewhat predisposed to overlook the drawbacks. Still, most accounts from residents are glowing. Residents extol the virtues of knowing who lives across the street and down the block; about neighbors who rush in to help in times of crisis. Raising children in such neighborhoods draws the most praise. Kids play safely under the village's eyes; there is no need to schedule play dates; it is easy to organize after school or recreational programs. Still, there are complaints about the "fishbowl" aspect of raising kids in such a close neighborhood and about clashes in parenting styles.

Decisions about the community are generally made by consensus and professionals consulting in the field encourage residents to resort to voting as only a last resort. Work is allocated on a volunteer basis and there seems to be an almost universal willingness among residents to contribute, perhaps not equally, but according to available time and abilities.

Those who develop co-housing tend to encourage a broad base of participants and to create cross-generational communities where singles, couples, families, and the elderly are encouraged to interact social and support each other. One of the emerging problems, however, seems to be related to the aging of members. In some cases the housing itself was not designed to accommodate increasing frailty. Some elderly residents (and these communities are now, at most, 17 years old so increasing numbers of original occupants are now in their seventies and eighties) complain that they feel isolated within the communities or that newer residents do not remember the work they put in when younger and now resent what they view as a drain on community resources.

Intentional communities are not easy to establish and they certainly will not be attractive to everyone, but the waiting lists at many of these active developments (not to mention the fact that several have spun off a sister complex within blocks) attest to their viability as a new way to approach the idea of neighborhood.