The first little pig was right!

William Campbell was working on his doctorate in music in Eugene, Ore., in 1997 when he and his wife were suddenly taken with the urge to live in an "earthy environment." So while Mr. Campbell was writing his dissertation, the couple began researching ways to build a home that would be more connected to the environment, one that would have a spirit they were sure they'd never find in a traditionally built house.

Campbell found his answer the day he walked into a local store devoted to natural living. There, on the bookshelves, he found a book called "The Straw Bale House." Intrigued, he and his wife began exploring straw-bale building, which involves stacking bales of straw into walls, which are then encased in plaster or drywall.

The Campbells learned it was a method of construction that, in the US, dates back to the 1890s, when Nebraska settlers on treeless plains used bales of straw to build sturdy homes. They also learned of a small but growing movement to bring back what proponents say is a remarkably energy-efficient and earth-friendly way of building.

"We went to a couple of wall raisings [of new straw-bale homes] in Oregon and Arizona," says Campbell. "They are kind of like old-fashioned barn raisings. It was very community-minded and very friendly. We got really into the whole idea."

So in early 2000, after graduating and accepting a job offer in Tucson, Ariz., Campbell, his wife, and their two children moved into a 24-foot trailer on a piece of desert property and began laying the foundation for their own straw-bale home. Over the next eight months, with help from friends and occasional assistance from paid contractors, the Campbells built the house they'd dreamed of: a 1,400-square-foot, three-bedroom, two-bathroom home, with passive solar energy, as well as a separate 400-square-foot studio for Bill.

"The whole idea for the house was to wake up informed by the earth," he says, "and to go bed thankful for all that the earth provides....

"When you walk into a house that's built for mass consumption, there's no feeling of love, no feeling of warmth or spirit," he adds. "But all these things are present in a house that's built by hand. It's especially true with straw-bale houses.

"There's a sense of openness in our home – almost a freedom – a warmth, a beauty. I can't describe it any other way," he says. "There's a sense of absolute peace and serenity."

Since the mid-1980s, more and more people have been drawn to straw-bale building for the same reasons as the Campbells: the user-friendly nature of the materials; the fact that straw bales are energy-efficient, with a high "R-value" (or degree of thermal resistance), which can reduce energy costs by as much as 75 percent; the aesthetics of thick walls and deep-set windows; and the environmental pluses of turning waste material into a solid home, instead of cutting down trees.

"It's an amazing material, and interest in it is ever on the increase," says Athena Steen, who, with her husband, wrote the books "The Straw Bale House" and "The Beauty of Straw Bale Homes."

"As more buildings go up, there are more examples for people to see," she says. "For those who've been leery of it, all they have to do is see one, feel one, and they're sold. It's dispelling people's notions that it's only good for dry climates."

The Strawbale Building Registry lists more than 1,000 straw-bale homes and buildings, a number that rises each year. Interest in such building is growing worldwide, from Mongolia to Egypt and from Japan to Chile. Aficionados say that straw bales work in almost any climate, wet or dry, because the bales are enclosed and set on a foundation.

"The three rules are good 'shoes,' a good 'hat,' and a 'coat' that breathes," says architect David Arkin, whose northern California firm has built nearly a dozen straw-bale houses since 1997. "Good shoes are a good foundation, keeping the bales up off the ground. A good hat is a good overhang on your roof, that keeps all but the most driving rain off your walls.

"And a coat that breathes is the finish that you put on the walls – stucco, cement, or earth plaster that allows moisture vapor to move through the wall so that if the bales get wet, they can dry out again," he explains.

Follow those three rules, says Mr. Arkin, and you can do anything with straw bales – a modern home, a "hobbit house," even a skyscraper. "For a lot of people, including seasoned builders," he adds, "it just makes sense."

Building choices – and costs – vary according to individual taste. The Campbells, who did most of the work themselves, built their house for $45 a square foot. (By comparison, traditional new housing costs, on average, between $100 and $175 per square foot to build.) Working with an architect or contractor, or choosing expensive appliances and finishes, can raise construction costs to $90 to $300 a square foot.

Houses can be built as load-bearing, which means the walls carry the weight of the roof, which was the case with the early Nebraska homes. (Load-bearing structures typically can't be built higher than a few stories).

Or they can be built as post-and-beam structures, in which a wood, steel, or concrete frame is built and bales are placed in the walls as "infill." The latter method can safely reach skyscraper heights, according to architect Arkin.

Advocates say that straw-bale building offers possible solutions for a number of environmental problems. For one thing, straw is a waste product, a cheap and abundant material, with as much as 200 million tons of straw underutilized or just wasted every year in the United States alone. According to the US Department of Agriculture, that's enough to build approximately 4 million 2,000-square-foot buildings a year.

In addition, the high thermal resistance of straw bales means that they keep buildings naturally warm in the winter and cool in the summer – which, in turn, means less burning of fossil fuels or use of other energy resources and less release of pollutants.

On a down-to-earth level, say experts, straw-bale houses are more durable than conventional materials on at least two counts: Bales are so tightly packed that they provide fewer havens for termites and other pests; and for the same reason, when plastered, they are fire-resistant because they don't hold enough air to allow combustion.

Catherine Wanek, publisher of The Last Straw, a quarterly construction journal, says straw-bale builders continue to learn from one another all the time. Although straw-bale building dates back to the 1890s, when hay-straw balers became commonly used, people have been building with natural materials such as straw, clay, and mud for centuries.

"There's a renaissance going on in terms of ... being able to use what's around us in our environment to build with," Ms. Wanek says. "That's what our ancestors did. It's what we call 'natural building.' "

Like many people in the straw-bale community, Wanek says one of the most appealing things about this kind of construction is that it tends to bring people together, both to learn more about building through hands-on experience and also from an old-fashioned sense of neighborhood and community.

"Community is something that comes up all the time in the straw-bale movement," she says. "People who do it are often seeking community and a great sense of community is built by working together.... More and more you hear that the world is a dangerous place, and this is the antithesis of that."

In Sunland Park, N.M., a desire for community – and respect for the environment – have been the driving forces behind a 47-home development of straw-bale houses for families with limited incomes. Tierra Madre, as the nonprofit development is known, was started in 1995 by a few local people interested in addressing the needs of poor families in an area where the annual median income for a family of four is $12,500.

Working with local families interested in building homes that were environmentally friendly and that also emphasized community self-help and collective responsibility, Tierra Madre eventually found land and started building. So far, the families have built a playground, and a community center out of straw, along with 16 homes that are now lived in. The homes – which are 1,500 square feet, with four bedrooms and two baths – cost about $45,000 each. Another 31 homes are scheduled to be finished by 2004.

"We're interested in creating a model about how people can live differently on the earth," says Jean Miller, a community founder and president of Tierra Madre. "We're trying to look at how we can live differently so we can preserve our natural resources for future generations."