The Pharaoh's attitude irritated the Lord, who sent hordes of frogs, flies, locusts, and other nasties to remind the Pharaoh of his displeasure. Of course, the Pharaoh later saw the error of his ways and Moses and his people were set free. And presumably, the land of milk and honey had straw aplenty.
But the use of straw as a building material predates Moses' voyage in the bullrushes by a couple dozen millennia. Anthropologists believe straw has been used as a building material for 40,000 years. They point out that tribes of hunter-gatherers in Africa still use straw to build temporary shelters and that semi-nomadic horticultural tribes use straw mixed with mud to plaster stick frame huts.
An important constituent of adobe, straw was used in adobe bricks found in Jericho that date back to 8300 B.C. Straw quickens drying time, reduces cracking, and increases the strength of adobe bricks. Adobe, of course, is still widely used today throughout the world.
In England, builders have used a mixture of earth and straw called cob for centuries. In Germany, builders still use leichtlehm, a mixture that relies on large volumes of straw which are dipped in clay and then pressed into a wood form. Here in the U.S., straw buildings appeared on the treeless plains of Nebraska shortly before the turn of the century. Made possible by the mechanical baler, which turned straw into compact bales, the Nebraskans found they could use the bales as oversized bricks, which, when stuccoed, made excellent houses with a minimum of wood.
Despite its utility, American farmers burn some 200 million tons of straw every year. That's enough straw to build two million straw bale homes. Usually burned or plowed under by farmers, straw from rice, barley, wheat, oats, or any other cereal grain can be used for construction. And straw bales aren't the only option.
Stramit, a British company, has been producing a compressed straw board that can be used for interior walls, doors, desks, exterior walls, and roofs since World War II. The company has licensed the technology in a number of countries including the Philippines, China, and Belgium. Discovered in 1935 by Swedish inventor Theodor Dieden, the compressed straw technology allows builders to do away with several processes. The panels can hold more than a ton of weight, so they can be used for load bearing walls that take up little space and are easily painted. The straw panels are also fire resistant and are good insulators.
Los Angeles-based Mansion Industries recently sent two pre-manufactured house kits that use pre-cut straw panels to Mexico. The company plans to produce house kits ranging in size from 260 square feet to 1900 square feet. The homes have pyramidal roofs and employ adhesives to join the edges. Tests have shown the material to be extremely durable. Although the Big Bad Wolf may be able to blow down some houses made of straw, the straw panel design is extremely earthquake resistant.
Mansion president Robert Glassco says, "Straw is a far superior building material compared to wood. It's fire resistant and insect resistant." Although the buildings are not currently in production, Glassco estimates that they will cost from 10 to 20% less than those using conventional building materials. The company is now trying to raise $1 million in capital through an initial public offering.
In small farming towns like Perryton, which lies a few miles south of the Oklahoma border in the Texas Panhandle, new uses for straw could provide a bonus for financially strapped farmers. Stramit will begin manufacturing compressed straw board at a plant near Perryton later this year. Farmer Myron McCartor attended the Green Builder Conference in Austin on March 1, to help promote the Stramit plant in Perryton. He says the region around Perryton produces huge amounts of wheat and therefore, huge amounts of straw - enough, he says, to feed 20 straw board plants. "Right now, farmers have to burn the straw or plow it under. With this product, they can find a market for their straw. So the straw becomes an extra source of income for them." McCartor expects the straw panels to be rolling out of the Perryton factory this fall. At present, Austin residents cannot get products made from compressed straw. But if the Perryton plant is successful, they could be available here within a few years.
In the Austin area, straw bale buildings have become a growth industry. More than half a dozen straw bale homes have been built over the past few years and many more are planned. The latest straw bale house, the future home of teachers Susan and David Darcy, is being built a few miles west of Oak Hill. The work is being coordinated by Bowerbird Construction, a new company that specializes in straw bale construction.
The four- bedroom, three- bath house, which will have 2300 square feet of living space when complete, will cost the Darcys about $40,000, with 20% of that amount going to pay for the septic system. "We bought five truckloads of straw for $1,300 and then we got one truckload of lumber and it cost $5,000," says David. Straw bale enthusiasts point out that straw bale construction uses less than half as much lumber as a conventional house, which reduces overall costs. The Darcys, who both teach at the Waldorf School in Oak Hill, are saving money by doing much of the work themselves. They hope to be able to move into the house later this spring.
Duncan Echelson, who started Bowerbird Construction a few months ago, says he got interested in the straw bale method after he decided to build a house. A macrobiotic foods distributor, Echelson was attracted to the straw bale method because it uses natural materials. He points out that using locally produced straw fits with the macrobiotic ideal of utilizing foods grown locally and the straw bales provide excellent insulation. Straw bale walls have an R-value of about 50. He also likes the simplicity of the technique which allows lower skilled workers to participate in the process. "There's nothing exotic about building a house. It's just a foundation, walls, windows, doors, and a roof." "This is a low-tech approach," he continued. "People can participate in something that is important to them and they don't have to go to school for ten years to learn how to do it."
As Echelson was talking, Susan Darcy and several other women with little or no construction experience were pounding wooden stakes through the bales to hold them together. While the men in the work crew did most of the heavy lifting of the bales, the women operated the bale press, aligned the bales and did other jobs alongside more experienced crew members.
The Darcy house was built in the "Nebraska style," meaning the roof will rest directly on the straw bales. Other construction styles use a post and beam structure that utilizes the bales as infill for the walls. In either method, once the bales are in place and have settled for a month or so, chicken wire is attached to the walls and three layers of stucco are applied to the interior and exterior walls. Again, Echelson explains that stucco is a low-tech procedure that can be done by virtually anyone.
Much of the credit for the renaissance of the straw bale technique goes to Pliny Fisk III, the founder and chief architect at Austin's Center for Maximum Potential Building Systems. (See related story) In 1987, Fisk, Matts Myhrman and several others built a straw bale building at Oracle Arizona, near the site of the beleaguered Biosphere II project. In 1989, Fisk oversaw the construction of a straw bale building at the Laredo Blueprint Farm, an experimental farm on the border.
Fisk wasn't the only one experimenting with straw. Builders in Arizona, New Mexico, and California were embracing the concept. Building officials in Pima County, Arizona are currently reviewing building codes for straw bale structures. The first commercial loan was recently extended to the builder of a straw bale structure in California. According to former Austinite and straw bale aficionado Steve Kemble, straw bale structures can be built for as little as five dollars per square foot or as much as $70 per square foot. At present, no straw bale buildings have been built within Austin's city limits. However, city officials say they are interested in the technology and are waiting to see Pima County's regulations.
The resurgence of straw is due to many factors. Rising lumber costs, interest in renewable materials and the abundance of straw make it an economical building material. And because disposing of waste straw often presents a problem for farmers, employing it in construction makes eminent sense. With its many advantages, straw may soon become as common in buildings as the 2 x 4. From the adobe bricks of Jericho to the high-tech prefab straw houses of today, straw has a future - just ask Moses.