Along the way they stopped to hold workshops and give (very brief) home tours. Some events drew hundreds of people. “It seems like everybody is fascinated by the idea of living in a tiny house,” said Mr. Shafer, who started Tumbleweed eight years ago. “But for a long time, I was just selling the dream.”

His business is still modest, but in the past year Mr. Shafer has sold five houses and 50 sets of plans, up from a yearly average of one house. The houses range in size from about 70 to nearly 800 square feet, cost $20,000 to $90,000 to build, and resemble birdhouses: boxy shape, wood siding and high, pitched roof.

Other builders also report increased demand. Brad Kittel, owner of Tiny Texas Houses in Luling, Tex., said he had built 10 homes this year, up from four in all of 2007.

Image Others choose to actually live in theirs, like Dee Williams, whose 84-square-foot knotty-pine house has a tight but cozy interior. Credit... Karie Hamilton for The New York Times

In recent years, small dwellings have begun to get the high-design treatment, which could attract more people. The London-based designer Nina Tolstrup built the 388-square-foot Tiny Beach Chalet, which has drawn attention on design blogs. One of the stars of the Museum of Modern Art’s current exhibit on prefabricated houses is the Micro Compact Home, a 73-square-foot cube by the British architect Richard Horden.

“When you build small you can spend money on higher-quality materials,” said Jared Volpe, a Web designer in North Ferrisburgh, Vt., who runs the blog smallhousestyle.com. Mr. Volpe said he is often amazed at how aesthetically pleasing many of the latest small homes are. In the year since he started his blog he has received increasing numbers of e-mail messages from people interested in small homes  a trend he attributes in part to the poor economy. “People will need to heat their 3,000-square-foot house this winter, and it’s going to cost double of what it did a few years ago,” he said.

For Mr. Janzen, a tiny house is not an immediate solution to his frustrations with large-scale living; he has no intention of cramming his wife and young daughter into 80 square feet. Instead, he plans to use the structure as an office, or park it on his in-laws’ farm as a weekend retreat, a more traditional use for tiny houses. But he will treat it as an “intellectual exercise,” he said, that will allow him to develop “an idea of the other extreme of size.”