I should build a straw home
out of straw blocks!!!!
Straw bale homes can bring down utility costs
January 6, 2008
Dear Jim: I want a natural way to build an energy efficient house without plastics, foams, adhesives, etc. Straw bale houses seem to be natural. Is the straw bale construction efficient for low utility bills? -- Gail H.
Dear Gail: Straw bale houses date back more than a century in the United States. Today, they are becoming more popular throughout the world because of their energy efficiency, use of a waste material and global warming concerns.
Straw is considered a waste product from farming, and it creates a disposal problem for farmers. The two most common types of straw in the United States are from wheat and rice. Straw bale sizes are typically referred to as two-string and three-string bales with the latter used more often for houses.
The costs to build a straw bale house are equivalent to a standard lumber-framed house. The straw bales are available everywhere. If you are lucky enough to live near a farmer who has a straw disposal problem, the cost is extremely low.
With the simple straw bale house construction methods, your family can do much of the wall assembly to lower costs. A three-string bale when placed on its side is about 23 inches wide. When packed to a normal density, it produces an insulation value of greater than R-50. This is several times more insulation than the typical insulated lumber framed house wall. Smaller two-string bales yield up to R-32.
With the thick walls and the properties of straw bales, the houses are very quiet inside. Depending upon the type of finishing material used on the interior and exterior, the walls breathe. This improves indoor air quality as compared with a standard house with tightly sealed, vapor-barrier walls.
Properly compressed straw bales are fire-resistant. There are enough air pockets remaining to create the high insulation value, but not enough to sustain rapid combustion. When the interior and exterior surfaces are encapsulated with stucco or concrete, fire has little chance to spread.
Soft plaster and gypsum finishes are attractive and are durable. The plaster has a comfortable feel and is easy to work with. There is a natural softness to the smooth curves and corners with this finish. Straw bale house walls can be self-supporting. The compressive strength of straw bales is high when they are stacked. Long threaded steel rods run from a horizontal roof plate down to a concrete foundation or slab.
When nuts are tightened on the rods, the bales are forced together. Another construction method, called infill, uses post and beam framing with the bales in between them for insulation only. Both construction methods produce a strong, yet compliant (for earthquakes) house.
The following offer information on straw bale houses:
Design Forward, 626-796-2566, http://www.designforward.net
Living Shelter Design Architects, 888-248-2114, http://www.livingshelter.com
Natural Building Resources 505-895-3389, http://www.strawbalecentral.com
One World Design, 509-838-8812, http://www.one-world-design.com
Syncronos Design, 505-898-9163, http://www.buildingwithawareness.comv
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