Cohousing design considerations: Models of development.

Cheryl Gladu
6 min readAug 11, 2020


This is part of a series of essays related to cohousing. For more information, see the introduction here.

Photo by Jon Tyson on Unsplash

A hard truth faced by many with dreams of living in cohousing is that currently, cohousing is not a model of affordable housing. It feels like it should be, but I find myself having to explain time and again that it’s people with some means that typically live in cohousing communities. Moreover, they often go to great lengths to live in these communities, including leveraging their personal finances in difficult and creative ways.

So cohousing is not affordable housing. Not in North America, not now. There are glimmers of hope, for sure. There are accessible units in market neighbourhoods. Some exceptions prove the rule. That said, on the whole, cohousing is a form of housing development that takes place within and in some ways despite the current housing market. Until we address some of the systems-level issues that make money more expensive for those that need it most, we are going to be dealing with this issue.

One thing that people hoping to make cohousing more accessible might consider is that cohousing communities don’t have to be new construction projects. Most of the communities that we admire are new building projects. All but one of the projects in Canada adopted what is known as a “project model.” This is a model whereby the community acts as its own developer. These organizations seek out and secure land and financing, organized professionals in a manner to design, seek approvals, develop, and build these neighbourhoods. But new construction is expensive. Part of what makes it so is that borrowing money is expensive. It’s even more expensive the less experience you have applying it to new building projects. So while new communities may not have to pay a developer’s profits, they also don’t typically benefit from a developer’s often hard-earned access to cheaper money.

The heavy up-front investment required to purchase the land and pay for the soft-costs of development (e.g. professional fees and services), means that this model of development requires a substantial cash outlay by many of the members of the community, often before they can be sure the project is going ahead. Moreover, participants are often jointly and severally liable for the financial obligations of the development project. This great leap of faith can surely present challenges for communities of wildly divergent levels of wealth.

Another way to deal with this is to adopt a different model of development — one that doesn’t require so great an up-front investment. Not as sexy perhaps, but it can work — and it can work now, for more people. A number of models of cohousing development were described 20 years ago by researcher Dorit Fromm and include the project model (described above), the lot model, the expanding neighbourhood/retrofit model, and the streamlined model.

In the case of the “lot model,” a large site is purchased and subdivided into lots, which are sold on the general housing market. These market homebuyers are responsible for the design and construction of their own private homes. The sale of each lot contributes funds into a common pool for the construction of the common facilities including the common house. This requires less of an up-front investment by the community as a whole. An alternate approach to this model is to hold the land and commons in a trust and have members pay monthly fees to this cooperative entity, which is collectively managed. Again, access to suitable financing will make this more or less viable an option for your group.

A third development model, the expanding community (also called retrofit cohousing), occurs when members buy adjacent homes in existing neighbourhoods and encourage others to join the community. Overtime the fences are removed, creating a large common area made up of the rear yards. A prime example of this model is N Street Cohousing in Davis, California. The first two houses were built in 1986 and the community has grown to include 19 households. In 2005, a common house was built to serve the established community. It took 19 years to put the common house there — but it’s there. A similar approach happened in Canada in the case of Ottawa’s Terra Firma, where two groups of townhomes were connected with a common house several years after the townhomes were renovated and occupied. Some other homes in the same neighbourhood are now adjunct members of the community.

Terra Firma (glorious gardens unavailable for photo), Canada’s only current example of retrofit cohousing.

If you are still married to the idea of a new construction project, you may want to consider the “streamlined process.” This occurs when the concept is spearheaded or guided by an experienced developer, who agrees to a fee for the development services provided. This model is exemplified by the collaboration between the Wonderland Hill Development Company and Cohousing Solutions, in Boulder Colorado. In such a case, the development process is streamlined by having an experienced cohousing community developer control the site, much of the design, and the financing. This arrangement can be more cost-effective and limits the amount of deliberation needed by the residents, which can be helpful as there is really no end to decision making in the process of building community. Provided the developer understands the purpose and nature of cohousing, working with an experienced developer provides the group with several advantages as a key success factor in the multi-family real estate development is having a high prior success rate.

Research has demonstrated that projects that make use of alternate models of development may be more accessible and allow for a younger more diverse membership. And yet, when I sit down with forming communities the default assumption is that cohousing must be new build (and without the involvement of a developer) because of the notion that cohousing is sufficiently physically distinct from the standards of housing construction in North America. I think we have to move away from this mindset. Cohousing is an intention. That intention is manifested in the spaces that are created together, but how these look and feel can be as diverse as the communities that create them. A lot of our historic neighbourhoods have “good bones” for an expanding community or retrofit model — smaller homes, more green space, and a need for a little love and attention. The same can be said about some condominium projects. It wouldn’t take much effort to reimagine the use of what is already there. Best of all, if the project starts and “fails” you’ve likely made an existing neighbourhood more vibrant in the process of organizing, talking, and dreaming.

Crossing the chasm to a place where cohousing becomes much more commonplace is going to take some creative thinking, novel models, and a commitment to the ends rather than the means of cohousing — creating connected resilient communities built on collaboration.


Fromm, D. (1991). Collaborative Communities: Co-Housing, Central Living and Other New Forms of Housing with Shared Facilities. New York: Van Nostrand Reinhold.

Fromm, D. (2000). American Cohousing: The First Five Years. Journal of Architectural and Planning Research, 17(2), 94–109.

Irigoyen, S. (2019). Under construction: Rising interest rates are expected to be a potential threat to industry growth Apartment & Condominium Construction in Canada About this Industry. (July), 1–31.

Sanguinetti, A. (2015). Diversifying cohousing: The retrofit model. Journal of Architectural and Planning Research, 32(1), 68–90.



Cheryl Gladu

PhD, MBA. Assistant Professor Human Enterprise and Innovation (TRU). Focused on tools that empower people to collectively live simpler richer lives.