Miguel Elliott created this combination oven and seating alcove in the yard of his Petaluma home.

Petaluma artist uses cob technique to craft functional, whimsical forms from clay

When Miguel Elliott is working, he?s dancing. Dipping his toes into a pile of mud he begins the stomp, an ancient two-step that is part of the process of turning wet earth into walls with his two bare feet.

It?s a 10-minute dance to turn this earthen mixture into building material ? usually done to a background of Arabic music or Native American chants.

Then he will take the squishy clay and slap oozy handfuls onto a frame of adobe bricks and/or broken chunks of concrete. At this point, the real fun begins as he sculpts, kneading and working and forming the wet earth into rounded forms. After days of primal play in the mud, he will have something that will bring long-term pleasure or comfort ? a dome sauna, an enclosed bench, a pizza oven or a little backyard meditation hut.

This is cob, a prehistoric building technique taking simple clay soil and mixing it with sand, straw and water. It may be ancient but Elliott?s ?Living Earth Structures? have a back-to-the-future quality to them. They are so primitive they are positively hip ? the ultimate in sustainable and local construction.

?It?s the granddaddy of green building,? says the 37-year-old builder and community organizer, who last year returned to his hometown of Petaluma after 18 years of wandering the globe, learning and applying this ancient craft.

He built a school out of cob in Patagonia, a nightclub and yoga studio in Chicago and a cantina in Guatemala. He taught cob to recovering substance abusers in southern Thailand.

For the past year, in addition to doing custom work, he has been leading workshops in Sonoma County, showing others how they can build their own backyard projects for little money, using the earth from their own property.

For the all-earthen sculpted interior of a nightclub he was commissioned to do in Chicago, Elliott didn?t even have to leave the city. He dug out the brown earth from Wrigley Field, proudly creating what he calls ?Baseball-Mound Clay.?

For many of his own projects he takes the earth right from his own back yard in western Petaluma, mixing the clay with straw cut from a nearby hillside. He makes adobe bricks from hand-made molds and leaves them to dry in the sun ? all on site.

Elliott?s pieces have a distinctively Latin American look, with natural forms and earthen tones he achieves with a mixture of linseed oil and powdered iron oxides, a natural material from stone. Each piece is plastered over with a smooth surface of sand and earth.

His signature pieces are large semi-circular high-backed benches, often emanating out from a wood-fired oven. These centers of warmth and cooking often are sculpted into symbolic figures of inspiration or whimsy. For a Guatemalan bar, he created benches that radiate out from a central Buddha whose arms reach out and embrace whoever is sitting there.

He has done eagles and condors and for his own back yard he sculpted a Luma, that mythic creature of Petaluma lore ? you can?t ?Pet a Luma.? And indeed, his Luma is so enticing you don?t want to pet her but you might want to snuggle into her warm embrace. Elliott inserted a copper tube into the oven so that when he pours water into the top, it races through the hot earthen interior and comes out only seconds later boiling hot enough to steep a cup of tea.

The thick walls of a cob oven are every bit as effective for cooking pizzas and bread as a far more expensive brick oven, Elliott maintains, achieving a temperature of up to 650 degrees. He makes bread, casseroles, cookies, cakes and even the Thanksgiving turkey in his.

And while he can custom-build a wood-fired cob oven for clients for $2,500, he?s just as happy to teach people how to make one themselves. He has upcoming workshops at Green String Farm in Petaluma on May 23 and 24 and another open workshop in Petaluma with the group Daily Acts on May 30 and 31. He can also be observed making adobe bricks today during Living History Day at the Petaluma Adobe State Historic Park.

Cob is essentially the same process as adobe. But while adobe is made into uniform bricks, cob is sculpted, so it can take on many shapes. The method has not gone through the rigorous structural testing necessary to allow it to become a legal, commonly used large-project building material yet, says Elliott. Adobe is covered in the building code, but is allowed only with reinforcing steel. He believes that given enough time, cob will be more common.

?You basically have to build a concrete house but just with adobe and you have to add 5 percent asphalt to the adobe mix,? Elliott explains of adobe. ?So it?s perfectly legal. And cob could be the same.?

Elliott keeps his projects small at under 120 square feet, so building permits aren?t required.

But within that space, he can make his large benches ? which are really like snug little open air rooms. He also makes small steam saunas complete with indoor niches for candles and skylights from recycled bottles, as well as smaller decorative benches and ovens. The ovens he can build right on a trailer, so the heavy structures, weighing hundreds of pounds, can be transported easily to parties and gatherings.

Elliott first learned about the ancient building technique of cob, an old English word for ?lump of clay,? back in 1994. At the time, he was working with Americorps in Arcata right after graduating from Humboldt State University, where he studied art and music. He wound up doing small cob models and sculptures with troubled youth. The possibilities of working with earth on a grander scale led him to Oregon, where he trained in the technique with the Cob Cottage Company in Cottage Grove.

Further inspired, he traveled deep into South America?s Patagonia region, where he worked for months building a kindergarten school, all of earthen cob.

In Central America, he built a little cob pizza restaurant for a woman at Lake Atitlan who had lost everything in a hurricane. After living for a time in Thailand, he found himself in Chicago, doing both high- end and community work with earth.

He sculpted an earthen interior for a yoga studio, which led to a commission creating what he describes as ?the largest indoor sculpture in the world? ? the interior of a nightclub called The Butterfly Social Club. It is 1,200 square feet of complete cob ? from interior walls and tables, to benches, arches and even the DJ booth. The work on both the studio and club did not include the building structure itself, but most of the interior design finish.

While doing a community project in Chicago for AIDS patients, then-Sen. Barrack Obama came by to check it out.

Ask him what the advantages are of building from a material you can basically dig out of your own yard, and Elliott will produce a list of 40 good reasons. It?s fun, it?s affordable and it?s easy, once you?ve learned the basic techniques. It lends itself to community projects and is also about as green as you can get.

?It?s very empowering, that somebody can really build this themselves,? he says, ?and in the process of building you can invite your friends and kids to come and help.?

You can reach staff writer Meg McConahey at 521-5204 or

Meg McConahey

Features, The Press Democrat

Like most everyone, I love a good feature story that takes me somewhere I’ve never been or tells me something I don’t know. Where can I take you? Who in Sonoma County would you like to know better? I cover the people, places and ideas that make up Sonoma County, with general features, people profiles and home and garden, interior design and architecture stories. Hit me up with your tips, ideas and burning questions.


UPDATED: Please read and follow our commenting policy:

  • This is a family newspaper, please use a kind and respectful tone.
  • No profanity, hate speech or personal attacks. No off-topic remarks.
  • No disinformation about current events.
  • We will remove any comments — or commenters — that do not follow this commenting policy.
Send a letter to the editor

Our Network

The Press Democrat
Sonoma Index-Tribune
Petaluma Argus Courier
North Bay Business Journal
Sonoma Magazine
Bite Club Eats
La Prensa Sonoma
Sonoma County Gazette