A greenhouse is generally considered to be a house for plants. But for Tokyo-based architect Hiroshi Iguchi, a greenhouse can be a very pleasant home for people, too, and he has built several such projects to prove his point.

Iguchi’s latest glass development is a utopian experiment called Millennium City. On a plot of open farmland in Chiba, a two-hour drive from Tokyo, four giant greenhouses comprise an environmentally friendly commune. This eco glass village is the product of several workshops that Iguchi organized in order to come up with an innovative solution to Japan’s housing situation, which is highly polluting and socially isolating. “Millennium City allows people to live closely together, yet in privacy, and enables them to enjoy a lifestyle in harmony with nature,” Iguchi explains.

Small wooden pavilions in each of the four greenhouses function as living areas. Each features an enclosed room elevated on stilts, not unlike a tree house, with a ladder leading up to the entrance. Underneath, the open platform appears to float just above the earthen floor. There are no formal designations for these spaces; it’s left to the user to decide how to use them, from sleeping in the elevated hut to reading, relaxing, gardening, or entertaining below. A communal kitchen is built into one of the greenhouses, and a separate pavilion accommodates the shared toilet and bathing facilities.

Iguchi’s dedication to environmental conservation and an earth-conscious lifestyle is further evident in the commune’s source of power: Supplementing the electricity supply, the greenhouses use solar energy for lighting and heating. Trees help monitor the interior temperatures of living areas (see sidebar), and solar panels made from plastic bottles provide heat for the water, ensuring that residents don’t have to suffer through cold showers.

In order to bring his somewhat offbeat community to completion, Iguchi established a nonprofit organization to corral others into helping develop Millennium City. This not only created a community of like-minded people, but also helped keep costs low. The land for the project was secured as a 20-year lease through a volunteer who also happened to be the president of the Japanese Agricultural Association. Other aspects of the buildings were secured through similar means: “Through the personal connections of our members,” Iguchi elaborates, “many materials were donated or supplied at low cost. The trees were a gift, as well as all the kitchen furniture, the bathroom fixtures, and many other amenities.” Though the glass houses were built by a greenhouse manufacturer, volunteers built the wooden pavilions, thus significantly reducing the total building costs for the project. As a result, the entire complex was completed for about $470,000.

Millennium City is structured on the assumption that the pavilions will be rented out for either temporary or long-term accommodation. With rents at about $50 per month, the pavilions offer an affordable seasonal getaway or reasonable year-round lodging in the inflated Japanese real estate market. “I can imagine a family with children moving into Millennium City. The father can commute to Tokyo for work and have something peaceful to look forward to when he comes home in the evening,” says Iguchi. But the glass village assumes a community function as well. There is an art school, for example, where tea ceremony, flower arranging, and painting classes are held. A variety of classes on ecological agriculture and exchanges with agriculture students are also planned.

There are other environmentally friendly benefits of the glass village, as Iguchi explains: ”The fact that this one place facilitates so many different functions is in itself already ecological. The huts can always be recycled or reused, either by dismantling and reassembling them in a new location, or just by moving them intact.” Iguchi emphasizes that to save energy, he avoided using high-tech instruments whenever possible. It’s cheaper to do it the old-fashioned way, both by reducing to a minimum the space that requires heating and by adapting one’s daily routine to the outside light and temperature. As Iguchi says with a laugh, “Our ancestors actually lived a very environmentally friendly life.”