Build a Straw Bale House

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Straw bale Home construction

Straw bale Home construction

 "Really? Build a house with straw?"

STRAW BALE HOME-BUILDING Build a House with Straw? Yes! Seriously. Building a house with straw may sound like a simple, primitive, or idealistic concept worthy only of  ”Three-Little-Pigs” jokes and the imagination of children’s tales, however straw bale construction in the modern world is becoming serious business —and quickly moving into mainstream construction. Such construction has become accepted and more increasingly important as energy costs keep rising.  

What is a straw bale house?

A straw bale house is a house built with walls of baled straw. Ordinary oat, wheat, or barley straw is compressed into compact, square bales with a mechanical farm baler at harvest time. The bales are uniformly sized and amazingly strong and durable. The straw bales are simply used as building blocks, piled, and fastened into position, and the resulting wall takes the place of standard “stick” wooden framing. Straw bale construction is now fully accepted as a substantial, even superior method of construction under building codes in many jurisdictions in North America. Advantages of building with straw bales include:
  •   Strength. Straw house buildings are strong. The stucco-covered straw bales will easily meet all of the roof and structural weight requirements.
  •  Inexpensive to build. Straw houses can be built for as little as $40.00/square foot, depending upon design, other materials, far less costly to build than other standardized construction methods.
  •  Save building materials. Depending upon the specific method used, a straw bale home with load-bearing straw walls uses approximately 50% less wood and framing material than a conventional stick-framed home.
  • Straw houses can be built upon many variations of foundations built of concrete block, wood, or upon a simple cement slab.
  • A straw building is very heat-efficient, with straw- bale walls rating from R-40 to R-60 insulating value, depending upon the straw used an the size and quality of the bales. An 18″ thick bale provides an R-value of approximately R48. (2) A straw building is environmentally efficient, easier to heat and also much cooler in summer heat.
  • Straw buildings are rated far higher for fire resistance than regular home construction and will easily pass a 2-hour fire exposure test and result in lower insurance costs.
  • Straw is a completely renewable resource, coming from the process of growing wheat, oats, barley, or  other similar grains.
  • Vapour barrier plastic sheeting is not necessary. Straw bale walls “breathe” allowing the passage of moisture vapour. Interiors may be simply painted with a breathable paint to allow moisture to go through the walls.
  • Insect or rodent problems do not develop. There is little or no food value in straw, and the walls are sealed with stucco and plaster.
How do you build a House with Straw Bales? To build a house with straw in the simplest terms is to use baled straw as the main component in wall construction. After a foundation and floor is installed, wooden plates, typically 2×6 or 2×8″ may, or may not be installed around the perimeter, and bales of straw are then stacked straight, level and carefully, pinning them into place. Exterior timber framing, post and beam framing, or partial standard framing may be included to provide extra load-bearing capacity, install windows and doorways, or to help simplify some aspects of complicated design criteria, but straw bales by themselves will provide all load-bearing capacity required.

In a normal load-bearing straw wall, the bales are stacked using standard masonry methods; that is, piled to alternate the joints for maximum wall strength. Dimensioned lumber framing is installed where windows and doorways are required. The bale layers are pinned using steel reinforcing rod, wooden doweling, or equivalent bamboo sticks. Double top plates are installed flush with the exterior and interior walls, fastened to the bales with strapping or metal rods, and the roof trusses and roofing components are then installed as in normal construction.

  The straw walls are then covered with a wire or plastic mesh that may be “sewn” to the surface using wire, or “stapled” to the straw. The wall is then plastered with cement or lime stucco. Interior walls are wired, similarly finished with plaster, or may be completed with sleeper/framing and drywall construction. Rooms in a straw bale home are usually framed using standard framing methods and dimensioned lumber such as 2x4s. Additional stories may be added to a straw bale house by installing the second story floor joists on the top layer of plates as required, installing the second floor deck, and proceeding to build the second story walls with straw. Roofing on a straw bale home usually includes a wider eave to help keep moisture off of the walls. As a construction method, straw bale building is fast becoming more popular and accepted by lenders, insurers, and builders. If desired, a little “truth window” on the interior of any wall may be installed to display the straw nature of the building and convince your friends that yes, indeed, your house is built with straw! Worried about the durability or your straw home falling down? Some straw bale homes in existence are known to be over a century old and are still in perfect condition.

Is that Incoming I hear?

Photo By Williamborg 17:56, 24 May 2008 (UTC) (Photo taken and edited by uploader.) [Public domain], via Wikimedia Commons   +FacebooktwitterredditpinterestlinkedinmailFacebooktwitterredditpinterestlinkedinmail

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