Straw Building Code

Building Codes affect all of us; this is an appeal for donations to fund a straw bale building code effort to create a chapter in both the International Building Code and International Residential Code.   Please Read On!

Americans spend over 70% of their lives in buildings, and nearly 50% of the energy used in American homes is for heating and cooling. Even as power plants and energy providers find new ways to deliver cleaner energy, once that energy reaches our homes much of it is wasted through poorly insulated wall systems. As we replace dilapidated housing, we need more energy efficient, healthful, sustainable alternatives.

Advances in conventional construction techniques and materials improve home energy efficiency but have a high environmental cost. Most manufactured insulation materials are energy intensive to produce, made from petroleum, must be transported long distances to a building site, and have unknown long-term impacts on our health, or the health of our planet. But there is an alternative.

Straw has been used for millennia in traditional buildings throughout the world. Combined with clay and sand to form masonry walls—many cob and adobe buildings are five-hundred years old and older and still used today! More recently, late 19th century American Great Plains pioneers were inspired by circumstance (plentiful grasslands and wheat fields, very few trees) and the invention of the baling machine. They used straw to build comfortable, energy efficient homes that are still used today, one-hundred years later. Renewed interest in straw bale building in the 1980s continues to this day, and has carried on that pioneer spirit of ingenuity driven by necessity.

But today, we face different daunting circumstances: rising energy prices, fuel source uncertainty, and climate change. Our desire to build with local, low cost, long lasting, renewable, simple materials like straw addresses this challenge.

  • Straw is an annually renewable agricultural “waste” product; the woody stems left over from the harvest of wheat, rice, barley, or oats—crops grown throughout North America.
  • Enough straw is grown in the United States that if we used only one-half of it for building, we could still build ten million 2,000 square foot homes each year! For comparison, there were fewer than Seven-hundred thousand new home starts in 2011.
  • This endemic American building system has spread around the world--today, there are thousands of comfortable, energy efficient straw bale buildings though out North America America and the world.
  • 18” and 24” thick straw bale walls have an R Value of at least 30, and because they are plastered on both sides, combine insulation with thermal mass for an incredibly stable wall that buffers temperature swings.
  • Straw sequesters sixty times more carbon than is required to grow it, giving it the lowest Carbon footprint of any insulation material today.
  • Straw bale structures are beautiful, offering unique features like deep window recesses that serve as seats or shelves, and soft, gently curing walls that reflect light quite differently than painted drywall.

Straw—a locally plentiful, natural material—could be used in place of foams and fiberglass, but we face a significant barrier on the path to sustainable building: Building Codes. Several western states have adopted straw building codes, but too often plastered straw bale walls are regarded as provisional or experimental. We need to promote a straw bale building code with wider appeal so more designers, builders, homeowners, and code officials have better access to this remarkable building system.

Martin Hammer (California Straw Building Association), David Eisenberg (Center for the Development of Appropriate Technologies), Mark Aschheim (Santa Clara university), Kevin Donahue (Structural Engineer) and others volunteered their time to present a Straw Bale Building Code to the International Building Code (IBC) this past year, but the effort failed in October at the last step in the process. We still need a plastered straw bale wall system to undergo a computer modeled FEMA P-695 Analysis—a new structural test.

We are trying to raise $10,000 to complete this analysis and cover the travel expenses of those advocating for an International Straw Building Code on our behalf. Our next opportunity for code approval will be in late 2013 and then again when the next IBC cycle begins in two years. Meanwhile, we must complete research, testing, and further refine the code.

Please help make a Straw Bale Building Code part of the IRC and IBC. Paired with the education and outreach efforts made by many organizations and individuals, code adoption can dramatically increase the number of sustainable, energy efficient buildings that we’ll leave for future generations. Here are some ways you can help:

  • Visit the CASBA website to make a donation— scroll down to find various levels
  • Fundraise as a member of Team Building With Straw in the May 2013 Climate Ride
  • Spread the word and encourage friends, family and colleagues to join CASBA or make a special contribution toward these specific efforts.

Thank You for your additional help with these important projects,
CASBA Advisory Board