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Why a Mud Anarchist Like Me Supports the Cob Code

by Michael G. Smith

I met Ianto Evans and Linda Smiley in Oregon in the spring of 1993. They had just started the Cob Cottage Company and were getting ready to build their second cob home. The three of us spent most of that year hand-sculpting a tiny cottage out of clay, sand, straw, and lumber salvaged from dumps and burn piles. We spent only about $500 on materials. Building permit? No way! We weren't going to let the government stand between us and our right to house ourselves in a manner that was as gentle on the planet as we could imagine, while also giving full reign to our artistic self-expression.

I spent the next five years co-directing CCC and teaching cob workshops on dozens of sites around the Western US and Canada. What kept me at it were many of the same goals and interests that attracted students to our hands-on classes. Cob was a way that people with little or no building background and few resources (except time and some kind of at least temporary land access) could learn to build their own homes free from bank loans, toxic chemicals, and the tyranny of professional designers, builders and bureaucrats. By building tiny homes from locally harvested materials, we were empowering ourselves, enriching our communities, and keeping our negative ecological impacts very low.

We never got a building permit for any of our projects, nor consulted an engineer. When I moved to California in 1998, I began to be more concerned about the possibility of earthquakes damaging cob buildings. By then, some cob projects were being permitted and there was increasing interest among cob enthusiasts in pursuing this option. When Bay Area architect John Fordice asked me to join the Board of the Cob Research Institute, a new non-profit dedicated to developing a cob building code, I reluctantly agreed. My primary interest was to safeguard cob as a truly ecological building system. I didn't want to see it follow the path blazed by permitted adobe and rammed earth buildings in the US, which were increasingly mechanized and incorporated large amounts of industrial materials such as cement, rebar, and asphalt emulsion. Luckily, the rest of the group was on the same page.

John's initial budget projected that we would need to raise half a million dollars to pay for the testing necessary to support a cob code. I was dubious that a scrappy group with no track record would ever have access to that kind of money. I also assumed that the conservative culture of building officialdom would resist our efforts. I figured we were taking on a lifetime of possibly fruitless struggle. And it wasn't all that clear to me what was to be gained. For me, cob building was more a way to inspire people to make conscious decisions about consumption and to manifest their values through the work of their hands than to change the building industry at any scale.

As the cob code slowly gained momentum through the decade of the 2010s, I was surprised by several things. One was that the process of code writing and adoption was much more democratic than I would have guessed. Although the major players in code development are manufacturers and industry groups pushing for the use of their products, it is possible for anyone to propose and defend code changes. We got to know activists (such as David Eisenberg from DCAT), architects (including Martin Hammer) and engineers (including Anthony Dente) who had dedicated much of their lives to opening up the code to more ecological alternatives. They had much higher opinions of our chances of success than I would have credited and threw their talents and experience behind our efforts. Once the right people were in the room, I was amazed at how quickly things started to happen.

Also, there was a growing coalition of sometimes unexpected allies who supported our work. By partnering with faculty and students at university engineering departments, we were able to get much of the needed testing done for free, which reduced the cost of code development to a fraction of the initial estimate. Even building officials were supportive, giving advice and lobbying colleagues. By the time our code proposal came to a vote of International Code Council members (mainly building and fire officials), an astounding 93% voted in its favor. A likely reason was the officials' enthusiasm for fire-resistant building solutions amongst escalating wildfire losses. Some of the “us vs. them” dichotomies in my mind were beginning to break down. If building officials and engineers could be fans of earthen building, then who exactly was the enemy?

The current version of the cob code adopted as Appendix AU of the “International Building Code” is far from perfect. So far, the testing we have done on shear resistance in cob walls allows the code to prescribe several combinations of rebar and steel mesh to keep cob walls from falling down, depending on the severity of expected earthquakes. (As we are able to test the efficacy of bamboo and plastic and natural fiber mesh, those options will be added to the code.) The code requires that an engineer approve designs in moderate to severe seismic zones, which can be a big expense for an owner-builder. Probably most significantly, the usual code requirements remain in place for all non-cob portions of the building, including foundations, roofs, windows, electrical wiring, and so on. Building more affordable and ecological options into these parts of the code is an enormous task that has barely begun. Anyone trying to build a deeply green home using the cob code at this point is likely to end up disappointed.

A cob house constructed following Appendix AU today would not be a perfect manifestation of the ecological and social principles that inspired the founding of the Cob Cottage Company 30 years ago. Still, I increasingly understand the point of the exercise. Especially if built at large scale, these structures would be an immense improvement over building norms. That point was made clear to me a few years ago when a massive plume of toxic smoke from the burning town of Paradise surrounded my home and the homes of hundreds of thousands of Californians. All those houses lost, people and animals killed, families displaced. All of those plastics, glues, and chemicals wafting through the air. Much of that tragedy could have been avoided if the homes had been made of fire-resistant cob. At this point in our history, large scale adoption of even the most sensible practices is only possible if they are legal.

I also recognize that the code is a constantly evolving tool that is being incrementally improved. Immediately after our success with the first version of Appendix AU, CRI began working on improvements for the next 3-year code cycle. In collaboration with Quail Springs, we conducted a fire test at a laboratory to prove what people have known for millennia: that cob doesn't burn. We have also been doing thermal testing on straw-rich cob mixes. Their higher insulation value will allow cob buildings to be permitted in more climate zones. These changes and many others will eventually find their way into the code. The primary obstacle at this point is securing the funding for more tests.

Finally, I believe that CRI's work will serve environmentally motivated builders who can't stomach the compromises still embedded in the building code and permitting process. Data from the many laboratory tests CRI has conducted has been distilled into the code's safety recommendations. These can guide safer cob construction practices even for builders who choose not to get a permit or hire an engineer, especially once CRI is able to dedicate time and resources to writing explanatory materials for builders and designers.

There is still a long way to go to manifest our vision of healthy, dignified, ecological housing for all. (Not to mention the overwhelming problem of equitable access to resources including land.) The cob building code is not a magical tool that can accomplish any of these goals on its own. But I am sure now that it is one more serviceable tool in the bucket – a tool that I will continue to invest time and energy into, probably for the rest of my life.