Charles Montgomery wrote:

A few years ago, a few dozen of us came together to launch an experiment that we hoped would tackle middle-class housing affordability, social disconnection, and climate change all in one go. We set out to create our own village in the heart of the city, a place designed to nurture friendship and care among neighbors while shrinking both our cost of living and greenhouse gas emissions.

We knew this was a wildly ambitious dream. To bring it to life, we had to become real estate developers. We poured our life savings—and more than six years of hard work—into designing and building a cluster of homes that would be as efficient at reducing our carbon footprint as it was at generating strong social connections. To do that, we used passive house construction. We infused our building with social nooks and shared amenities, such as a kids’ room, workshop, and roof garden, as well as a common kitchen and dining room. Of course, to make the homes affordable for our group, we would need to build as tall as the City would let us: six stories.

...

Our housing experiment really is working. We enjoy our own small apartments but dine together a couple of times a week. We help each other out. Adults volunteer to provide after-school care for other people’s children, saving them hundreds of dollars a month. We are developing a culture of neighborly kindness and care. And, because we share walls in a super-efficient building, our carbon emissions have plummeted by more than three quarters compared to folks who live in detached homes.

As a private venture, our building doesn’t claim to solve the homelessness crisis, and it doesn’t provide housing for people on very low incomes. But it does make room for 50 people on land that previously housed fewer than 10, and at a fraction of the cost. And it does relieve the demand for other apartments and lower-cost housing in the city. Economists agree that buildings like ours are a key part of the affordability solution, especially if they replace more expensive housing in walkable neighborhoods.