The use of cob–a mixture of clay, sand and straw (or any similar plant fiber)–for building houses and other structures, is one of the oldest eco-compatible building materials of the human species and is also used by some birds, wasps, termites and other species, too. In August of 2023, I decided to build a cob oven for my wife’s birthday, which was one month away at that time. We did not finish the oven until eight months later, in April, 2024, due mainly to the fact that the cob froze in October, when we were not quite finished, and did not thaw out again until late in the month of April. We live in the northern Rocky Mountains of Montana, USA, and have real winters here. For a couple of days that winter the temperature got down to -40 degrees F. The other big reason that it took so long to finish the project was that we had a very busy harvest season in September and October, with many fruits and vegetables to gather and process.

The following video (in three parts) shows the whole process from start to finish, including the first complete meal cooked in the oven (we had baked some French bread in the oven prior to that to go with some spaghetti that we cooked in the house). The materials that we used to build the oven, including the stone base and cob ingredients (except for the straw) were gathered from the beautiful land that we live on. The wood for the oven door is from a slab of myrtle wood that came to me back in Oregon, over forty years ago. The two other exceptions to home-gathered materials are the fire bricks and the ceramic tiles, which we bought with money.

Part one: https://www.youtube.com/watch?v=zaYu8WxKFFA&t=9s

Part two: https://www.youtube.com/watch?v=QL6FyAkrrBA&t=5s

Part three: https://www.youtube.com/watch?v=gy0DF77bA_c&t=761s