Wednesday, May 28, 2008

News; Straw Houses: No Need to Fear the Big, Bad Wolf

In the story of the three little pigs, the one who built his house of straw did not fare well; the big, bad wolf huffed and puffed and blew his house down.

But builder Michael Furbish, who made his own home from bales of straw and an elementary school of the same material, says in reality, straw houses are not only sturdy but also good for the environment.

Straw—the stalks of plants like wheat, oats, and barley—is considered a waste material and is commonly used for farm animal bedding. But more and more people are discovering that straw baled into rectangular blocks is an excellent, inexpensive building material.

"Our mental picture is that a straw bale is light," says Furbish. "But each bale weighs about 40 pounds (18 kilograms). We stack them like bricks and then spray plaster—mud, essentially—on the inside walls to coat them one and a half to two inches [3.8 to 5.1 centimeters] thick. Then we put stucco on the outside. So a straw building is really like a fortress, and it is not going to rot as long as water is kept out of the bales."

There are two ways to make a straw-bale structure. You can build load-bearing walls with them, which means the walls support the roof. Or you can build a post-and-beam wooden frame that supports the roof and fill in the walls with straw bales.

Either way, the walls are there to stay. And they provide great insulation, helping keep straw homes in cold climates cozy in winter and those built in hot places like the desert cool in summer.

Straw is considered a "green" (good for the environment) building material because it is a renewable resource: A whole new crop can be grown and harvested every year, easily "renewing" the supply.

Also, planting and harvesting straw uses relatively little energy. "Most other building materials require a lot of energy use in production and manufacturing at a factory," explains Furbish. "With straw-bale construction, you are getting a building product without using much energy at all."

Furbish used about 900 straw bales for his family's two-story, three-bedroom house. His company provided straw-bale walls for the Friends Community School of College Park in Maryland. That project used about 4,000 bales.

When asked if there are any drawbacks to living in a straw house, like mice nibbling on the walls, Furbish points out that the straw is completely covered with plaster and stucco. Besides, he has a couple of cats on mouse patrol, just in case.

"It would be hard to find a wall system that will outperform straw," he says. Looks like the big, bad wolf is just out of luck.

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