The most important difference between cohousing and other types of housing is that, in cohousing, everyone is there because they want community. In an ordinary neighborhood, your neighbors may not be interested in being neighborly. In cohousing, your neighbors meet you halfway.
A cohousing community is managed by its residents, making decisions by a nonhierarchical participatory process such as consensus. Thus every resident has more input than they might in a homeowners' association where decisions are made by a board elected by majority vote.
In many cohousing communities, residents perform much of the work to maintain the property. The resulting cost savings may be used to lower fees, but often is used instead to pay for community-building things like an annual retreat, a monthly party, or child-care during community meetings.
Since a cohousing community is designed by, or in consultation with, people who intend to live in it, the design priorities are different than they would be if it were built by a developer who intended to sell the units and move on to the next project. A developer spends money on things that he/she hopes will improve sales, holding down costs elsewhere to maximize the profit margin. A cohousing community spends on things that will improve life in the community, holding down costs elsewhere to preserve affordability and income diversity.
A typical suburban house puts the parking in front, separating it from the neighbors, and the living areas in back, away from public space. A cohousing home reverses this.
A typical housing development consists of similarly sized units: one- and two-bedroom apartments or three- and four-bedroom houses. A cohousing community deliberately creates a mix of differently sized units, to attract households at different life stages.
A few cohousing communities are associated with CSA farms or other businesses, which employ a few residents. A few religiously oriented intentional communities have chosen to follow something resembling the cohousing model.
For the majority of cohousing communities, however, residents do not share incomes, or work at a business belonging to the community, and the community does not expect its residents to share any set of beliefs or religion. Diversity is in fact often an explicit value of a cohousing community.
Beyond encouraging potential residents to become familiar with the community and the concept of cohousing before buying or leasing, cohousing communities allow new residents to choose the community, rather than the community requiring a new resident to pass an application process.
Within constraints imposed by the site, the construction budget, and the local planning board or mortgage lenders, every cohousing community reflects the aspirations and objectives of its founders and their theories about what will foster community. The agreements by which the community operates are also drawn up initially by the community's founders, although these are more easily amended, with experience of what works in practice, and with resident turnover, than are design decisions, which can be quite literally set in concrete. Forming communities benefit from observing, and improving on, designs and agreements in older communities.
Some of the ways that cohousing communities may differ from one another include