Cob is easy to learn and inexpensive to build. It dries to a hardness similar to lean concrete and is used like adobe to create self supporting, load bearing walls. Cob has been used for centuries throughout Western Europe, even in rainy and windy climates, as far north as the latitude of Alaska. This ancient technology doesn't contribute to deforestation, pollution or mining, nor depend on manufactured materials or power tools. Cob is nontoxic and completely recyclable, which is important in this era of environmental degradation, dwindling natural resources and chemical contaminants.
Cob is one of many methods for building with raw earth, the world's commonest construction material.
It surpasses related techniques such as adobe, rammed earth pise, and compressed earth bricks both in ease of construction and freedom of design. Building with cob is a sensory and aesthetic experience like sculpting with clay. You can add on, cut out, or reshape at any time, even after the cob is dry. Cob is a recent arrival in the United States. Except for adobe in the Southwest, earthen building is virtually unknown here.