As communities around the country struggle to make more affordable housing options available for residents, Johnson said some cities are changing zoning laws to allow families to build another small house, or cottage, in their backyard.
For example, Seattle encourages families to construct backyard residences that can provide alternatives to apartment complexes. Denver is considering a similar plan, he said.
Not only are small houses cheaper to build, they are cheaper to maintain, Johnson said.
A full-year mini residence could be built for $30,000 to $60,000, compared to the $300,000 it might cost to build the average 2,500-square-foot single family house, he said.
When he lived in the 140-square-foot house (he moved into a 360 square-foot home when he married last fall), he said he paid no more than $30 a month for heating during the coldest winter months.
And it isn't just individuals who are taking downsizing to the extreme.
Shafer moved into an 8 foot by 12 foot residence of his own in 1999, but he said that when he married and had a child, they built a "palatial" 500-square-foot home next to it, for a grand total of 600 square feet between the three of them.
And he said his company designs 800-square-foot three-bedroom homes, with "a little personal space for each person."
Shafter said there's nothing he misses in his tiny homes, which come equipped with toilets and showers. But he acknowledged that de-cluttering a life to fit into a very small space doesn't necessarily happen overnight.
"It was a major life change. It took a long time to figure out what I needed to be happy and what stuff I could do without," he said. "It's all about tailoring functions to scale of occupants."
And even the champions of the small house movement concede that micro living isn't for everyone.
Sacrificing space means giving up storage, the ability to host dinner parties and large gatherings and, if you don't live alone, a good deal of solitude.
"One size doesn't fit all," Johnson said. "While a lot of people enjoy the simplicity and quaintness of small homes, some people want their privacy. There's always going to be that."
And, he added, living in a small house means abandoning the long-held notion that a big home indicates big success.
"In society, it's just peer pressure, you want to show that you're successful… Nobody is going to move into them if there's a stigma attached," he said, "Unwittingly, there are some changes that have to go on in the inside."