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Straw Bale Buildings Return to the Prairie
The arrival of the horse-powered baler in the 1880s — and mechanized ones even later — made straw a popular building material through the early 1940s. Schools, churches, homes and farm and ranch buildings were created with bale walls, reviving building techniques used centuries earlier in Europe and other parts of the world.
ResurgenceToday, bale building is experiencing a worldwide revival. Builders in Europe, Asia and the Americas are blending old techniques with new technologies to construct energy efficient, comfortable, easy to build, innovative and creative buildings. The uniqueness of building with straw bales is its compatibility with other building methods such as concrete, cob, adobe, timber frame and steel.
Tested at an insulating value of R-48 or greater — twice the insulation value of most homes — bales are energy-efficient building blocks. A bale with a thickness of 14 to 18 inches is also a natural soundproofing material. Nebraskan Lucille Cross spent her childhood in a hay bale house. She frequently tells the story of the time when the family was inside playing cards, unaware that a tornado was swirling outside.
Stacked and secured within post-and-beam or load-bearing structural systems, bales can be coated with stucco and plaster that preserve the bales and add structural strength. Typically, 300 bales are used for every 1,000 square feet of structure.
There is no need to wrap the walls to prevent air leakage. Conventional roofing can be used. Living roofs combining standard roofing materials with earth and compost to sustain plants and add mass. Full or partial basements, slab on grade or a crawl space are workable as are standard footings and foundations. Properly constructed and maintained bale buildings can easily last for several hundred years.
A bale building is ideal for passive solar design. Stuccoed walls absorb and store the day's radiated heat. Properly orienting a building on the site aids in solar energy gain, protection from winter winds and snow and summer storms and hot breezes.
Cheap to PriceyOpen interior space with few halls and walls helps keep material costs down and eases utility costs by allowing air to flow easily throughout all spaces with minimal equipment. Building costs can be highly variable, but generally range from $5 to $120 a square foot. The national average for new home construction is $53 a square foot. Homes constructed of bales have been built for as low as $5,000 and as much as $200,000.
There are other efficiencies in the use of straw beyond forming walls from a crop byproduct or binding crop residue into bales of standard sizes. The use of these crop residues creates new markets for something that would otherwise be burned, buried or left to decay.
Straw can also be chopped for use as a component of a "bioblock" — a mix of other recyclable materials including plastics and wood — used like a concrete masonry unit or concrete block. Straw can be compressed into board form for use as plywood, sheathing, flooring and other building products. Plants manufacturing products from straw have been appearing from Texas to Canada in the past several years. One manufacturer uses straw to create a variety of consumer products ranging from business cardholders and brushes to bird feeders and downspout splash guards. Of course, straw has been used as a binder in bricks, stucco and adobe for centuries.
The Straw Bale Association of Nebraska, founded in 1998, is a channel for information, a network for anyone interested in the revival of Nebraska's best building idea and a resource for balers, builders and enthusiasts. For more information about straw bale construction or the Straw Bale Association of Nebraska, contact Joyce Coppinger of Re:Build Associates, phone 402-483-5135 and 800-910-3019 or by email email@example.com ¶
Return to the Summer 1999 Newsletter