Question Can you really build a house with straw?
Yes, with dry, tightly baled straw you can build a durable, beautiful home.
The Three Little Pigs had it all wrong! Homes, schools, parks, and even businesses have used straw bales to build sustainable, durable and attractive structures.
Sustainable building, also called green building, is “the practice of creating and using healthier and more resource-efficient models of construction, renovation, operation, maintenance and demolition.” (U.S. Environmental Protection Agency.) Some home builders achieve this using materials that seem out of the ordinary. Straw bales are one of these alternative materials.
Building with straw is not new, but its use has been increasing. The buildings can be plain, fancy, large or small. They are easy to customize and lend themselves to artistic flourishes. Straw bale homes have withstood harsh climates and weathered well in cold, snowy winters and hot, humid summers. There are many straw bale homes around the world, some of which are over a hundred years old.
Advantages of a straw bale home over a conventionally built one include:
- They use a fast growing and renewable agricultural byproduct that is otherwise wasted.
- They contain fewer toxins than conventional materials.
- They have a high insulation factor that lowers the cost of heating and cooling.
- The homes can be easily customized to the owner’s needs, both practical and creative.
- The cost per square foot is reasonable, and depending on the building methods chosen, can be very economical.
There are two ways to build a straw bale structure: load bearing and non-load bearing. A load bearing house uses the straw bales to provide the structural support for the building. Load bearing structures are most appropriate in mild climates. A non-load bearing house uses lumber or some other material for its primary support. The bales then shape the walls and provide the insulation. Places that get lots of snow need that extra support.
In construction, the bales are first stacked on a foundation. They are piled on top of each other to form the walls. Next, a moisture barrier is applied. The final layer is of plaster made with a base of clay, lime, or cement. Paint may be applied, but is not necessary. What is necessary is to keep the plaster in good condition and to regularly inspect for cracks. If the straw becomes damp, the house can be ruined by mildew.
Straw bale houses are often built in a workshop setting. Everyone is guided by an expert who has been hired to supervise the project. The owner gets plenty of help to build the home, and the other participants learn how to build with straw. They also get plenty dirty while stacking the bales, making the plaster and smearing it on!
Who would have imagined that people could build earth-friendly homes from straw? There are many other alternative materials being used to build interesting and sustainable shelters: rammed earth, cob, papercrete, cordwood, recycled glass bottles, structural insulated panels (SIPs,) tunnels (for partially underground “earthships”), car tires, and even plants (for green roofs and living walls.) It is exciting to imagine what new techniques are in store for the future.
If only that Little Pig had known enough to bale his straw properly, he would still be snug inside. The Big Bad Wolf would never have been able to blow his sturdy little house down.
Published: 11/19/2019. Author: Science Reference Section, Library of Congress